I'm risking being hated, but here it goes.
I think it's perfectly fine making a full game plenty of characters and side quests. Actually, I want that.
Sorry for the poor comparison with an AAA game, but can you imagine The Witcher 3 without side quests? Some people only care for the main quests, yeah, but others will do every side quest they can find, it makes the game feel more complete even if you are just rushing through it.
There are some people here cursing the dev without ever spending a cent in the game and I never donated to the dev, so I can't complain either. But, I kinda of understand people supporting him feeling frustrated they didn't get a new scene from their favorite character, on the other side (here comes the hate) strategically I understand the dev milking them to get support through the entire game and not only the main quests.
The main quest gets completed and all scenes are available, so what now? A lot of people will just drop the support and many will lose the interest in the game, even those getting it for free. It still would be a lot of content to be created but with way less support and the game will just fade into abandonment, as usual. Remember, you are supporting the game not only your favorite character, although it's fine liking the game only because of it.
If we had access to The Witcher development a lot of people would be screaming "I don't care about this lady in Novigrad, I want to see what happens to Ciri" and "WTF is this GWENT shit card game? Where is the main quest?"
If you are spending money in this game and dislike my opinion, I can understand it, just ignore me.