partitions existed to negate the effect of FAT32 inherent ability to turn files into air. NTFS (the version on windows 7/2008+) can self heal on the fly these days.
also to locate your swap at the optimal location - which is irrelevant with SSD.
but it is not a bad thing since win7/2008+ can hot grow/shrink a partition without shutting down.
With multi-threaded i/o capability you could in fact increase performance in some cases with a partition or better yet multiple real drives since you can dispatch threads on more cores to do i/o. which is SQL server 101 on why you create a 'ton of mount points or drives if you are so inclined to store your database(s),tables within, logs for, and tmp. if you have 4 cores and only one I/O path then you'll dispatch 1 core to do the i/o and wait. if you have a program that can dispatch those to separate paths (logical or physical i guess it doesn't matter much). its likely those unused extra cores can dispatch i/o.
Much like how hyperthreading works - even if its 10% gain it is gain over not having it. and sometimes it is not gain at all - just depends on the application.
I'd just have two ssd drives or more in jbod given the state of raid controllers (really does it really take a year or two to do trim in intel matrix? they could bust that out in a day since its software raid).
so you have old tech; and new tech that is now at consumer level - to consider.