[3.P] The Summoner's Handbook: A Guide to the Pathfinder Summoner

[Larpus]

Well, consider that one of the strengths of the 3.5 Druid was being able to dump your Physical stats into the dirt and still fight at full capacity while Wildshaped, and a Synthesist can do exactly that plus evolutions to customize his combat capability and the ability to self-buff himself, it's quite powerful.

Well, that is somewhat what I had in mind when I said he could be a decent gish.

However, the problem I see is that unlike a Druid he can't really use some of his class abilities, especially Summon Monster (biggest problem being no option to trade it for something else like couple feats or more spells) and also, if memory serves me right, the druid gets some of the animals' feats for free, not to mention better spell versatility.

I guess that what really spoils it to me is not being able to trade Summon Monster for something else.

EDIT: Like a Mr.Hyde Alchemist can trade his bombs for sneak attack if he wants to.