I've just checked character vaults... Every alchemist have 5\5 bombs throwing but almost nobody has Invoke Golem and other powers.
In my opinion, golem is a main Alchemist's force - you can freely send him to enemies and strike them, stun them, heal golem then summon golem back or recreate without fear of fail - because your main character is standing on the stairs in safety. I've got only to level 24 so far - maybe things will change later.

Even more - on the insane difficulty golem-driver seems to be easiest character to play - golem has elite rank and I think he has no penalties to damage taken.