SFD's map editor, as of now, lacks many decorative tiles that deviate from SFD's dark and bleak art style, what I mean is that you can't really replicate, let's say, sonic with SFD's colour palette, it would just be plain impossible.
And of course, this doesn't need to be possible but I think there should be an option for players to be able to sink in tons of hard work to completely change their level's aesthetics to match another game or just to give their own level a completely unique aesthetic.
So, I present to you... The pixel, which would exist in all three categories of tiles, solid, foreground, background, and far background, so what is it? A literal pixel, which can be moulded into whatever you want and won't just use SFD's limited colour palette, instead, it'll use RGB colour values to determine it's colour.
To be easier to "mould", the edges of the pixel would be able to expand by dragging the edge like any other tile currently in the editor, this would make the process of making a tile less monotonous, like having to copy-paste it again and again just to make a damn line.
and for a more complex suggestion... after the tile is done, it can be put into a "tile group" which'll function like a normal group but it'll be able to expand and shrink like tiles.
Now, I have absolutely no idea whether something like I suggested is at all possible, for all I know, the devs might be laughing their asses off at the absurdity of my suggestion or feel shame because their limited game can't have a mere pixel as a feature, but that's beside the point, which is, take my shit with a grain of salt...
Okay, let's say it's not possible, I've been making backgrounds pixel-by-pixel with the BgDamage00A tile, and I hate that I have to copy-paste again and again just to make a damn line and I hate the fact that the colour of the tile can't get any lighter even though lighter colours exist in SFD's palette.
If the devs wanna go the minimalist route the least I want them to do is make a new "pixel" tile that has all the colours in SFD's palette and exists in the categories FG, Solid, BG and FBG.
Another good thing with the pixel tile is that, if you are just feelin' nostalgic but have no intention on making an entire level of mario world, because you just aren't talented enough to pull it off accurately, or you don't have the time, you can just make some of the tiles used in mario and upload it to the cloud and hope to inspire someone who's more talented, or has less of a life than you, to make a mario world themselves.
And this also solves all the tile suggestions, if you want a tile in foreground you can replicate the tile with the pixel, tile group it, and then post it on sfdmaps or something for fellow mapmakers to use.
Go On, Click Away. Signatures Are For Fools Who Haven't Said Enough! -Karl Marx if he had an internet connection