first I've heard of this idea

I mean important issues (not just an avatar bug) and lack of some features may cause some users leaves the forum. Rep system is good if it works like those rep systems in other universal forums (my suggestions).

For me, browsing all posts and advanced search are main concerns. Because neither GOG built-in search nor Google are helpful.

While it would be technically easier, it's still likely expensive enough that GOG don't want to do it, at least not until they see it as an essential overhaul. My advice about convincing current active members who knows IT to help with specific solutions is about as close you are going to get to find a real solution in a decent time frame.

That might be right, but I still stand by my advice: pick the most important feature and find IT people here that are willing to offer a potential solution.

...you dont say

We might be willing to offer, but there a certain contingent here that will flip out hardcore at the sight of any proposed (even entirely optional) changes. You had a chance to observe the whole process over the past few days. :)

Personal opinion is that there's essentially no chance at present for anything you suggested being done.

There wasn't much chance before Galaxy development started, there's even less of a chance now.
Taking people away from that to burn time and effort dealing with a widely dysfunctional forum with a comparatively minuscule number of users isn't a realistic expectation.

The forum has a number of problems, from the concrete technical aspects to what each person who uses it thinks it needs to be better.
Regardless, everyone has two options - deal with it, or leave.

I would like to see someone leave because someone made a better search function, that would be the day. :P

Sounds ridiculous, doesn't it? =) Well, I never thought I'd see someone leave the forum because someone else can now block other people IF they so choose. =) So you never know!