Since we don't know whether or not Juan or Wallace is going to the last gym leader, I'd like to see ORAS pull a BW, and have version exclusive gym leaders.
I really don't want this to happen. Wallace is actually involved in the R/S's plot (although not too heavily involved - he only leads us to the Cave of Origin but oh well). Obviously, he got a larger role in Emerald. But Juan did nothing related to the plot in Emerald, and is only seen inside the Sootopolis Gym, where we battle him. Because of that, I always got the feeling that Wallace was more 'important' than Juan, so I hope Wallace ends up as a leader in both games. Having said that though, I would like a Juan cameo to make an appearance.
Do you remember any other memorable characters (battleable or not)? The wintston family was a neat challenge and that meditite was no joke. I can also remember Jr and sempai with roselia/graveler and spinda/slaking, those 2 spreading teter dance all around and using slaking's brute force to just tear through anything. Also the fossil hunter was always a little strange to me. Why digging through his house? were there fossils there? the whole thing could fall!
The Winstrates were pretty cool - although I was disappointed that the family member in Victory Road (was his name Vito?) was addressed like a normal Cooltrainer. IIRC, all the other family members had 'Winstrate' as their title (e.g Winstrate Victoria, Winstrate Victor etc.). It's a minor detail - but yeah.
Speaking of the Jr and Sr duos, the trainers in the route with the Day Care are all memorable to me. I think all of the trainers except the Bug Maniac were rebattleable - so it was a great way to earn experience points (especially the Breeders with six Pokemon!)