I want to discuss progress in BG2 with someone who plays this game or had played and wants to write about it ? ?
Just write me a message.
My party is-

Main- Cleric (a little bit tanky with good strenght and wisdom)
Minsc
Jaheira
Aeire
Jan Jansen

- I wonder if I add sixth character if someone really interesting come into my way ...

Imoen is a good choice for a 6th member.
And you can have several NPCs join you temporarily until you've completed their quests.

Yes, i agree that Imoen will be a good addition once you rescue her. Until then, you should consider adding Nalia. She sucks as thief, since her thief level is only 4, but you have Jan, so you are covered there.
You are lacking a true mage, so higher level spells will be unavailable for some time, due to the multiclassing of Jan and Aerie.

I recently played through SoA + ToB (with aTweak and SCS mods) with only Aerie as mage, and the only battles in which lack of high level magic was a real problem was The Twisted Tune and the final battle in ToB.

But it may have been easier if I had never dumped Nalia.

Nalia is somehow not interesing for me - I would like to add some strong caster, i know Eowin will come but he is evil character and I have a good party.Unfortunately I have choosen Cleric as main character (played many times mage or sorc before) so I will have to find some mage / sorc as sixth.Or maybe Jan + Aerie will be enough (although they are both multi).

I was thinking about playing 4 characters party but for that Sorcerer/Mage main would be necessary.

I don't understand why people hate Nalia so much.

Granted, her thieving skills are very weak, but if you ignore that, she's just a mage with short bow proficiency and a nice ring.

I agree. She has that +2 AC bonus from the ring and she can also carry more than twice the amount of Imoen (120lb vs 50lb from her 14 STR). Though I would never choose her over Imoen from a RP perspective. My party usually has both of them in from chapter 4 onwards, if I'm not playing a spell caster myself.

I have the impression that it is a combination of her being viewed as a worse version of Imoen, combined with her general demeanor. Similar to how Anomen's attitude rubs some people wrong.

I d rather pick Edwin than Nalia because he is simply better mage isnt he ? Yeah he is bad but one can handle that.

Correction: he has a cheat item that gives him 2 extra spells per level.

I added Cernd to my group but that was not right decision and I will kick him soon - i have Jaheira and main Cleric character so his druidic spells are a bit useless.His shapeshift to werewolf is nice but I heared that it is not very strong later even he can shapeshift to greater werewolf.

Maybe I ll just wait for Imoen and earn some more experiences with just 5 characters party.

If someone interesting come my way I ll add him but since now, I met no really interesting character for me - Nalia, Anomen, Kogan ...

So I decided to have as many characters as necessary - i go with main cleric Loran, Minsc, Aerie, Jan Jansen - I will decide if I change him with Imoen or no, he is funny and better thief then Imoen.

I wonder how much stronger will my characters be in just 4 characters game.

There is nothing, thief-wise, that Imoen can't do. There are items, spells, scrolls, potions. Nothing she can't do. Plus she's the whole reason your journey takes you to Spellhold and beyond.

Unless you're just looking for vengeance on the jerk who nicked your soul. ;)

The arsehole approach. :)