Original SMK is in my all time top 10. I like it better than MK 64 and I think the series has gotten better as it's returned to some of the principals of the original (MK7 and MK8).
Best thing for me is when they bring back a SMK retro track in a new MK. I've got them all in my muscle memory so I can easily school people online in MK8 Donut Plains or MK8 DLC Rainbow Road.