Mother 3 because its basically the only way for westoids to play it

Super Mario Odyssey (no not that one)

It's unfinished and dead, but what is there is really fucking cool.

I spent last spring/summer completely obsessed with A Link to the Past Randomizer:
https://alttpr.com/en

There's something gratifying about completing the whole game in under 4 hours with Hello Kitty as your character sprite.

Most of the romhacks I play are either randomizers or kaizo SMW.

For randomizers, I recommend ALTTPR because ALTTP turns out to be a great game to randomize, and PK Scramble because the developer put a huge amount of polish into it and it feels so Earthboundy.

Kaizo SMW is not for everyone, but it's not an unapproachable brick wall, and it might be for you. Love Yourself is a beginner kaizo hack that's a real joy to play. Note that "beginner kaizo" still means you should have (re)beaten SMW recently. If you want a good laugh, "My QLDC Level" from the 2023 Questionable Level Design contest is a work of shitpost art (link is a pack, level in question is in the MM102 & Faro folder).

Any of drayano’s pokemon romhacks

pokemon crown, hopefully shitendo doesnt close it down before its finished

Ogre battle randomizer

Contra: Hard Corps US version hack that puts the hit points back that were in the Japanese version, so it's actually manageable.

My preferred hacks are for games that are N64 era or older.

The OOT mods that make use of the zelda 64 decomp project are pretty impressive e.g. Ultimate Trial and Indigo: Chapter 2. The Sealed Palace and The Missing Link are also quite fun.

I'm also quite fond of visual and gameplay improvements to older games (NES + GB/GBC) and Romhacking dot net has some I've kept my eye on for a while.

Robocop Texas Edition uses graphics based on the original arcade version, Castlevania 3: Aperture of Corruption is a complete overhaul of the original NES game, and Street Fighter 2 Deluxe and Sonic 5 improvement are both romhacks of bootlegs for the NES that improve various graphics and fix gameplay issues.

Both Pokemon Polished Crystal and Pokemon Red Plus Plus feature updated graphics (similar to gen 3), fixed gameplay, new mechanics, and various QoL updates.

Pokemon Emerald Z. Decent fakemon romhack that is not super difficult like Altair/ Sirius/ Vega.
Pokemon Unbound and Gaia for new region hacks.
I also have kind of a soft spot for Pokemon Glazed and Giratina Strikes Back. Mainly because they came out at a time when pokemon romhack game balance and stories were awful. Meanwhile Glazed was just a regular get all eight badges story while Giratina Strikes Back at least had some semblance of level scaling/ balance/ no Lv 80 vs your own Lv 40 pokemon bosses.