My thoughts,
I believe that many a bowie in the days of yore had chisel ground clips. There is one famous style, so famous that I have forgotten the name, that in fact is only found this way. I'll dig out the magazines and try to find a name for you.
As far as aesthetics go, most people aren't really going to care. If you want symmetry, then you'd better not go with a chisel, though. One thing I HATE about many double ground clips that I have seen is the point where the clip ends. If you get a "mini plunge cut", i think it looks liek crap and it looks to me like it could interfere somewhat with a hard stab. If you gently ease out of the clip, then it looks cool. A chisel ground clip with only one side of a deep plunge might be o.k. though.
I think, though, the decision is very important for what the knife is. I don't think there is much point in spending lots of time getting a super ergonomical handle that looks just perfect, with a 1500 grit hand finish, decorated guard, and so on, and then do a chisel clip. It may look like you are just skimping out. Why put all that work in, just so you can cut corners at the clip. Then again, that bowie style I was mentioning (Searles? I dunno) looks just fine, and they fetch high prices.
To sum things up, I'd say that a chisel clip would be more than fine on a "combat grade" bowie. But if you are going to dress things up a bit, spend some extra time makign sure a chisel clip fits in with the rest of the knife (the "total package" theory at work here.)