hi guys
awesome work
once again i mind you nowaday that you gays have a hard and laudable effort, it is better that its consequence has a good and proportionate quality in respect to your effort. for this purpose it is necessary that game be at least in full HD (1920*1080) and everything lower than this, would be
alack in respect to your effort (regardless of increasing advances of screen and image quality such as 2k, 4k and 8k).
so i want you to think about it. as far as I know your HD sprites has maximum 400 pixel in hight and it is inadequate for full HD, because in most of the original MK games, the characters are indwelling
half of the screen (Refer to the following pics), so half of the full HD hight is 1080/2 = 540 pixel and this is far than your 400 pix characters.
furthermore as far as I know if mugen game build based on the 1920*1080 and later want to have low res game(f.e 1280*720) it is easily possible by work on some text file like mugen.cfg and system.def, but its inverse is impossible (higher res is impossible without having more high res sprites)
as far as I know other efforts on HD mugen games observe this (here you can see HD mugen sprites that have more than 500 pixel in hight:
http://parsemugen.webnode.com.br/download/characters/)

in this pic (original mk1 arcade) the character hight is 0.53 screen hight.

in this pic (original mk2 arcade) the character hight is 0.54 screen hight.

in this pic (original mk3 arcade) the character hight is 0.52 screen hight.
thanks for your attention