I'm being sarcastic. It falls flat enormously on what you get on install, the installation defaults are not sensible or look nice, Playnite expects each user to puzzle his/her way through the learning curve of dealing with different add-ons and a pile of settings, many which are not obvious, to make things work like they should off the bat.

But don't fret, I'm not just slamming it, I wrote a rant here that walks you through the process of installing it:
https://www.gog.com/forum/general_beta_gog_galaxy_2.0/cant_connect_to_steam/post59

A couple of things I'd change if I did this again -
I recommend these metadata plugins from the "addons -> browse -> metadata sources"
Universal Steam Metadata
Xbox Metadata Provider (if using Game Pass)
Metadata local (for non-english, it doesn't mean it gets them from _local drive_)

I don't think these plugins are useful that are recommended by eMixedNiteMc, but this is purely personal preference.
Systemchecker - Shows if you meet minimum requirements for the game. This is something you should look into before _buying_ the game.
News Viewer - Kind of useful, since it shows updates, DLCs and the like, but here it's not integrated in the details page, you have to click it open from the sidebar.
CheckLocalizations - Useful if you don't want everything in American, otherwise just extra download stage.
ScreenshotsVisualizer - Adds an extra button to the sidebar so it's not integrated, you probably would be better served by opening Steam client and using that with the screenshots.

For metadata there is now "official store" option in the "settings -> metadata" selection, but Playnite wants to use IGDB because of open source politics or something. I recommend ticking "steam store, official store, xbox store and IGDB", in that order. You can plop local metadata first if you want non-english descriptions.

You can set everything to do that using the drop-down menu and clicking "apply to all".

Using "official store" seems like a non-brainer, but e.g. Ubisoft/EGS description may be couple of sentences. Also the cover images are different between stores, so if you get it from Steam by default and use steam target aspect ratio preset for Settings -> Appearance -> Grid View -> Cover art, the game art does not have black (blue) bars in the grid view.

to avoids Feelings Being Hurt, someone made a big effort a couple of years back to kludge some kind of database together but now all you pretty much need is local metadata and universal steam metadata and box metadata (if you use game pass).

A Redditor said "not everyone thinks eMixedNiteMc looks nice", which is fair enough, but I'd like to see what "everyone" thinks looks nice, then. The eMixedNite, for example, is supposedly about the same as MC version, except for the video playback .. However, it looks quite ugly as it is and the five colour themes the author suggests do not really help. eMixedNiteMc has this neutral gray/black background with white texts by default, much like Steam. Install it and it looks Okay, at least as far as colours go.

Would you consider Playnite as a launcher versus an inventory manager? For those with physical media, Playnite would be relegated to launcher.

Does it have How Long to Beat information?
Can you make dynamic lists , like steam, but filter on whether a game is present in another list?

Say I want to see games that I have started but haven't finished, the filter logic for this "UNFINISHED" list might be"

Game is played but not in "FINISHED" list.

For example.