I see where you coming from.
I know alot of people that enjoy or will enjoy this game when it’s released because it’s a midleground between overwhelming PoE and watered down D3. Complexity-wise i think it’s sits right besides Grim Dawn which is perfect, even though both games do some things different.
So regarding Idols, they really are a good way to push your build this little extra.
I can’t speak for all classes but i mostly played acolyth and most of the Idols are usefull and some really can make a build super great.
I wouldn’t call them game changing or game breaking, basically they just give a lot of specialized stats for a certain playstyle, which allows you to focus the rest of your usual gear towards other stats.
(For an example, there is an Idol for the Lich’s Aura of Decay( which deals Poison Damage to yourself) that gives massive amounts of poison resistance, so you basically can go for other stats on your regular gear instead of stacking poison resistance on every other gear pieces.
Some Idols also give special proc’s, but what most Idols have in common are they revolve around a certain skill or mechanic of the class.
There are also some pretty general Idols which are also ncie in some situation, since you can stack multiple Idols.
All in all i would call the System a really good addition to build Depth and more items to hunt.