All this is obviously been discussed but I wanted to throw my 2 cents in
First off Construct Essence to Construct Exemplar Should be a 1 feat investment that scales with Artifice levels. Its not fair to ask a Fleshi to give up 3 additional feat slots to what a Warforged gets for free, with almost no draw back. This is a class based on construct feats and enhancements, the 3 feat requirement is just poor game play if nothing else.
Second Give Arcane Empowerment back to all Artificers at 20, this is a half hearted enhancement and hardly usable in game. Give the Arcanotechnician a decent Capstone.