Tile preview window

I have this big spritesheet with 16x16 tiles and it’s pretty hard to see what they look like at normal size.
Yes I can zoom the tile window, but then I can only see a tiny section of the whole spreadsheet at once.
It would be really handy to have a tile preview window such that when I put my mouse over a tile in the tilesets area, it previews it in bigger scale.

For example, my tileset is to the right, my mouse is on the tree tile, and on the left is a bigger preview window.

image

Alternative suggestion: allow having two (or more?) tileset views with different zooms and scroll positions, so that e.g. I can keep my two most-used sections of the tileset in view at once, and/or have a zoomed-out view to help me navigate the zoomed in views more easily.

Having the option for either or both of these would be great, since they address different styles of browsing tilesets.