I am of the personal opinion that dithering, as a practice, should never have been a thing, ever. I've almost never seen it not look sloppy, even back in the CRT days. I even did a graphics update of SMB (released here), SMB2j, and Triforce89's SMB Special hack to remove the dithering on the pipes, as it was the only place in the game that dithering was used.
As long as you're focusing on only doing 1 release, I have a request. Can you include the feature where pressing B on the title screen allows you to start at any world (or, if you're including sram, any world you've beaten)? This was the main reason I played Messatu's and Triforce89's version over yours and Karatorian's when I did my layout fix hack, and it is my favorite feature of the Super Mario Game & Watch.
If you're worried about patches coming out right after yours, just as a heads up I will likely be using Triforce89's graphics. I love how he struck a balance between SMB and SMB2j, along with some beta sprites, to make SMBS feel like SMB 1.5. You don't need to account for this; just encourage people to make addendum patches instead of stand-alone patches.