It would be nice to bring back the ability to specify ReSharper cache folder (both system and solution) like in 1.65. It's possible to improve R#'s performance by installing RamDisk and pointing R# to place cache files on it. This will speed up all kinds of cache seeks. I think with current average memory size per machine (I think 1G is the minimum now) it's easy to reserve 128MB for ramdisk in order to improve performance.
What do you think?