Don't need Aerosmith in specific, though it would be a nice callback, and i think that is more on the record label than aerosmith itself. But i really mean more of the visuals and rock in general in the soundtrack. Like Jack Black said, you can't kill the metal.
Problem with getting a DOA6 at this point is that I doubt that TN can improve on DOA5LR enough to justify it. Apart from some environmental textures, etc. DOA5LR still looks better than the other 3D fighter Tekken 7 IMO. If DOA6 drops and it's not leaps and bounds better than DOA5LR, people will whine and complain about that.
They can make better models, better textures and better animation already... Improvement on stages is a must in general. Now gameplay wise, doa5lr is too solid, i don't imagine how it can be improved upon, maybe change some movesets and expand variety.
Also, a new game would also give TN the opportunity to give the game a new netcode that is good, include new characters and expand on the ultimate and LR added characters. And honestly, is a good time in general to release fighting games, i feel that they're getting more press than a few years back, and also in general would give a chance for new people.
Stages could be improved. Honestly, DOA2U's & DOA3's (and some of DOA4's) stage designs were fine and could serve as templates for future stages. Graphics would probably be better than DOAX3's, though likely just a mild step up (remember also that the game engine has to maintain a consistent 60FPS, even with all the explosive dangerzone shit going on). As for gameplay, what I'd recommend is:
Tighten the mechanics: I.e. 1. Remove the auto-retracking bullshit on "linear" strings 2. Make sidestepping flow better with linear dashes or backdashes (think of how SS is like in VF or Tekken for instance) 3. Make it so a character in an airstate NEVER gets hit by a low attack ever 4. Remove the ability to move at R1F 5. Remove the stupid angled wall hits or anything else that unfairly halts an aggressor's offense
Don't get me wrong though, I am all for a DOA6 at this point, but I don't want TN to rush it and predict it will either release late 2018 or sometime in 2019. The biggest thing from a DOA6 release is that it would reinvigorate the 3D fighter scene along with the DOA community. However I want a future DOA6 to be successful for years to come, as opposed to a rushed stopgap because some people are bored of DOA5LR.
I think we all want a fully fledged game that had proper development time and budget. I think, at this point in time, this is more "easy", Koei seems to be more willing to invest into TN.
Yeah, but all Koei-Tecmo cares about is making money off of the game, I.e. Money off of DLC sales for the DOA ladies. There's a high chance that DOA6 may end up being more of the same in that respect. However, let's hope that a proverbial DOA6 is more like DOA5 Alpha and less like 2014 DOA5U with the fetish DLC train.