That's the problem with SNK, they made way too many awesome fighting games XD
Last Blade 3 would be awesome, as would Garou 2. OTOH, they just barely escaped extinction after 12 and considering that they're sticking to post-render pixel art (like they have a choice, after going all in with the new engine), they aren't too likely to have the manpower to do so many new characters (or do you want kof 12 all over again???).
I do hope next the next KoF will have better backgrounds than 13. Call me nuts, but I think the older SNK games had much cooler backgrounds than nowadays. For all the HD hype, the stages (however cleanly done) are kinda vanilla. At least the stages that came with the DLC characters were a huge improvement.