Pillars of Eternity - No regrets after the latest update.
The Witcher 3 - No regrets whatsoever.
Tyranny - small regrets there because of the lot of DLC and for a time the lack of upgrade options, but made me wait for Pillars 2 until they release the Definitive version.

I think Wizardry 8 is the only game I've paid full price for on GOG. I nabbed it as soon as it was available because it is an all time favourite of mine and the second PC game I played. I'd been waiting for it to be released by GOG. Nostalgia and fun all the way.

To be honest there is nothing currently I'd pay full price for. Three reasons:

1. Can't afford to - I have to budget buying new games.
2. It will be on offer at some point. My budget says 75% or under £5 is the best time to buy. I will sometimes make exclusions, but they're rare.
3. I have so many games in my library to play, I don't really need to buy anything which doesn't fit my purchasing criteria - apart from those rare exceptions when I just can't resist.

The one thing which makes me say Bah! to my budget is when I add up how much my husband has spent on wine in a week. If he's spent £25 or more on enjoying wine, I think I deserve a game. :P

Games I recently-ish bought for full price.
Devil May Cry HD Collection (pre-purchase), Monster Hunter World
Games I'm planning on getting for full price: Agony, Dragon's Crown Pro and Ni No Kuni 2

Never happened to me, I think. From the same reason as Breja - well said!

And the only games bought on day one here was NecroVisioN series, but it came with 75% launch discount, so quite far from full-price ;)

Broken Sword 1 and 2
Thimbleweed Park

Many. One game I even bought several times on Day 1 at release price: System Shock 2, because I was so happy it was here finally and I wanted to give away a few copies.

Then GOG introduced regional pricing. As inhabitant of a high-price region I felt cheated and stopped buying at full price. I didn't buy any game at full price since then. Instead I wait for sales.

I would, and I have. I do it when I want to play the damn game.

I don't care about the "first wave". Having playtested several games, the meaningful "first wave" is really beta. Everything else is bullshit marketing. And I don't have offline friends who are into videogames fullstop, not to mention a specific videogame at a specific time.
I really don't like the notion of "supporting the devs" as it's used in sales culture -- it kinda >implies a weird mix of e-begging and charity. Look, impersonal-you, devs set the list price, and if you can't pay the fucking list price, you don't get to play the fucking game just yet. They are neither asking for nor getting charity, they just made a good fucking game and you fucking bought it. It's no more "supporting the devs" than buying booze at the corner store is "supporting small businesses".
Finally, holy fuck how can you people even call yourself gamers if you think all games are interchangeable. "I already have a game, why do I need another one." Why indeed.

However:
All 3d action goes on the wishlist because of the potential controls issues and motion sickness. I bought The Witness (a puzzle game!) on release and it nearly killed me.
All survival games go on the wishlist to see if they have balance issues.

The last game I bought at full price was Iconoclasts. It looked awesome and I wanted to play it on release, which I did. I ended up hating it for the plot and characters, not for its production values. It wasn't my personal failure of judgment, and it wasn't related to the lack of reviews, so the fact that the game ended up sucking is not evidence against buying games at full price or on release / late preorder.
My worst on-release purchase was Cuphead (it had a 10% discount tho) - I can't advance in that game at all. Sure it's pretty, but the prettiness doesn't justify the $$ when the content is only accessible on youtube for free. This was more of a mistake, as I should've probably waited for all that "brutal and unforgiving" shit to surface.

I am now looking forward to Wildfire, Eitr, Hornet DLC and especially Children of Morta. I'll buy each of them on release (provided they don't get released on the same day, of course).

Have you really never done that yourself? I'm not talking about supporting CDProjekt or something like that or buying something you're not really interested in to "support the devs" but paying full price for something that you know is good instead of being cheap and trying to get it for the lowest price, because it was made by individuals that you respect and that you want to stay in business? Or because you thought their ideas are so awesome that it has to be rewarded?

I paid full price for Neverwinter Nights when it came out. Never regretted it, it was a game that just kept on giving thanks to the community.

Because we don't need your permission to consider ourselves gamers?

Someone who hoards games like crazy is no more of a gamer than someone who only ever has a single game in their backlog. Amassing stuff doesn't make you better at your hobby, unless you just want to be a collector. But digital games I will never see as collector's items.

Until a few years ago I paid them all full price. Then the economic crysis came, and a while after that cronic unemployment and struggles with real mafiosi and lobbysts - I'm lucky if I can gat a daily job every now and then, and I am outright banned from certain places because I stepped on the shoes of big fishes.
So now, as much as sometimes I feel guilty for not giving worthy developers the money they deserve (nobody can understand their struggle better than me), I can buy only DEEPLY discounted games.

Mortyr 4: Operation Storm (which wasn't a big deal, since price of release was in Poland 19,99 PLN) - very short game, but for it's "reputation" - suprisingly fun.

Eador: Master of the Broken World - ugh, I admit that I regretted a bit this choice. Due to the fact that I was playing a LOT in Eador: Genesis I was too much attached to "original", despite the fact that MotBW had normal save game feature (lack of it was REALLY annoying in original Eador). Later I've played in it a bit more and I've realised that it's, aside from poor 3D graphics and some lacks, quite enjoyable "remaster". But I could simply wait until some better discounts.

Sonic Mania - not necessarily "full price", because I've bought pre-order, which was slightly cheaper, but nevertheless - I'm not very proud of it. I've finished game only once and had enough, not to mention about sneaky, backstabbing DRM Denuvo (about which nobody knew).

Avernum 3: Ruined World. - Ah, what a great game. While Avernum 2 was a bit repetetive comparing to first one, this is very fresh and tasty title, definitelly worth to play (and pay full price).

THere were also a couple of games which I've bought in "day one" release on GOG, but due to initial discount they're rather not qualifying as "full price" (well, I should remove Sonic Mania from the list :P).

Ok, I think I get what you mean. It does indeed sound somewhat patronizing or entitled that someone (incl. myself) grants developers the "mercy" of paying the price they are asking for instead of waiting for them to sell out their products, and then kind of boasts about it. I guess it comes with the oversaturation of the market and the sales culture, but of course that's not really an excuse.

I did that as well. Hadn't found the giveaways in time not to.