Mostly just agree with the others. Pounce is awesome, Synthesist is good if you just want to make the fighter sad but regular summoner is stronger due to action economy. Wild Caller is absolutely worth it.
For your summoner, look at the Eldritch Heritage feat line, you get Skill Focus as Half-Elf anyway. Arcane bloodline gets you a familiar, which can later become an Improved Familiar that shares your UMD ranks. Marid bloodline sucks initially, but at level 11, you get Imp. EH and pick up "Water's Fury" for an at-will standard action 60 ft line AoE that does some damage and blinds for 1d6 rounds, save halves damage and negates blindness. Since you have spells for range, the familiar is probably more useful. You can also get Evolved Familiar feat.
Eidolon...you want pounce and as many attacks (ie, Arms) as possible. Claws, if not doing manufactured weapons, which is hella expensive. Flight, improved damage, reach (on at least one attack, so you threaten further), the +2 natural armor, size bonuses, str bonus...all are great evolutions. You can never have too many evo points.