I started to think that YuffieXReeve would be a good pair up. Both are weird and a little towards the outskirts of the group. She works for him now and they both get ignored quite a bit. Plus i recon that her poncho outfit is the remains of cait siths mog
I must say I was intregued by Yuffie and Vincent at one point, but meh, he's not right for her. (oh and FYI she is 16 in VII, 18 in AC and 19 in DOC)
Aeris and Tseng, was another one I sort of liked. But i'd rather see him hook up with Elena.
Reno and Rude....obviously
Lucrecia and Hojo, she went there and thats the only cool thing about her.
My friend always wanted Barret and Tifa to hook up.