Requimortis
The closest we will ever get to the old games is Resident Evil 4. However, if people were that desperate to have the formula that made the series famous to begin with, they should be writing letters or emails to Capcom instead of spending all their times on forums griping about something no one here has the power to change.
They did it with Resident Evil 4 and Resident Evil 5 and although I've finished two campaigns in Resident Evil 6, there's no sign of alternate costumes. I still have a little more to go through so I will let you know then.
I think Capcom went in a new direction was because people were complaining about how it was played. We had that formula for about 7 games so it was no surprise that it did get stale after a while and why the community embraced 4 so much. Personally, I like the old formula, but that's just me, but I do appreciate how 4 was able to give some new life into the series (I loved that inventory arranger.) I wish that 5 kept some of the same elements 4 did like the inventory arranger or how the game paused when you looked at it.