When I bought my current printer a couple of years or so ago, since they ALL produce eye-candy quality prints, the #1 priority in choice of models was 'ease of refilling the ink wells'.
I ended up getting a four-color Canon printer that uses the BCI-3xx inkwells, which are the easiest and least messy of all for refilling that I know of. They have a double-plus in that there are zero electronic parts in the wells, which are completely separate from the actual printing heads, so they don't have to be reset in any way. The only 'trick' to it is to hold the cartridge so that the filler and outlet holes are level with each other until the plug is put back in.
Mike