While technically the better build, I don't really like dropping my concept for something just because it works better.
Basically think of whether or not you want to be up close as well. If so, there are a few options here. Two that would work well enough are both options for a few levels of cross class. Either option can make use of Teamwork feets as its has suggested.
1) You can go the unarmed route, which I think could look awesome. Three levels of monk if you are lawful. Now if you aren't, there is the Martial Artist class, which allows you to be non-lawful, but replaces some abilities. There is a bit of a problem with this depending on the DM though. You want the level 3 clear mind ability to give you access to a feat. I forget what it's called, but you treat have your monk levels as monk levels for determine unarmed strike damage. Martial artist loses Clear Mind. On Paizo's site, however they did say it's perfectly reasonable to drop some archetypes abilities in favor of the original class ability.
This will keep up Summoners partial base attack, allow you to use wisdom to your AC, increased move speed, and some nice boosts to your saves. If you take a fourth level, your saves will be radder, and you'll get the +1 AC bonus for monk level four. Really though, 3 levels of monk is all you need to make this effective this route. Though if non-lawful, and DM won't let you keep the mind ability, take four levels of Monk for the first damage increase.
Math will get awkward for flurry of blows though, when calculating your base attack, your Monk Level will be used in place of your monks B.A.B., but your B.A.B. for summoner will be calculated as normal. It'll essentially amount to a nerfed Flurry of Blows.
2) Otherwise, few levels of Fighter or one of it's variants. Really any straight Melee class. Cavalier could be very helpful for it's full base, and it's different abilities could be of benefit to keeping hate on you and your Eidolon if that's the goal. I prefer option one if only for the saves and I love monks
If you yourself don't want to be on the front lines, remember your summon monster from your spell lists can still be summoned with your Eidolon out, so they can aid him on the front line. It's only the Summon Monsters you get as a spell like ability that can't be out at the same time.