In my opinion, the hack must have a rating of at least
4.5 in order to qualify. To be fair that is an arbitrary number but it is a good indicator of what seperates an exceptional hack from a great one. SMW has so many modifications with much variety so we must only choose those ones which are considered by the community to be the best. Then we need to narrow it down to those ones which have interesting strategies. Nobody wants to watch left-to-right levels for 30 minutes or so. In addition to this the TAS must be exceptionally made (particularly with regard to entertainment) in order to justify acceptance of the hack. Please note this is all just subjective and I'm not a judge or anything but it seems sane at least.
You can sort the hacks via rating using
this link.
My recommendations:
Anything by Anikiti (Japanese hacker who makes modifications that are
exceptionally difficult (not kaizo level), with clever level design and custom stuff)
Hack (gimmicky but short hack that could make for some interesting strats)
Shipwrecked (very open hack)
Return to Dinosaur Land (very good level design hack with some interesting strategies. I was working on this but I don't know if I will continue. The RTAers are running this currently so we can share strats)
The 7th Annual Vanilla Level Design Contest: Collaboration Hack (Hack comprised of lots of levels made by separate people. I think it could be interesting)
Bowser Rampages Again
Super Mario Omega
Super Mario Odyssey (it's a demo but SO well known)
Gregor's New Super Mario World
As well as TSRP and MIX series. In particular the MIX series has potential for craaaaazy strats, as shown by Mister, ISM and other's runs, which have inspired me in the past.