My main aversion to working with hacks is I'm always preoccupied by the idea that limited ROM space will limit the size of levels and what I can do with it.
If it's any consolation, in SMW, you can use a maxiumum of 96 levels on the overworld and 512 areas in total, each of which can be up to 32 screens in length (varies depending on if it's a vertical level and/or uses Layer 2, though) and has no limit on the amount of objects and enemies that can be put in. Within reason, of course. There's usually a cap at about 84 sprites in a single area, but using that many in the first place will probably cram so many sprites onto the screen that the game experiences slowdown, and you'll never have to worry about putting too many objects in a level unless you like fill every single block with a tile. If you use up too much space in the ROM, Lunar Magic will automatically expand it, so you don't need to worry about expanding it manually.
One of the hacks I created, Super Mario Infinity 2, is widely regarded as the longest SMW hack in existence, and I didn't even have to use all of the areas (though I came somewhat close!).
Anyway, as I just implied, I've created two full-length SMW ROM hacks, so of course I like SMW Hacking. I'm currently working on my third and final one, and no, it's not SMI3.
