All skills will be new, redesigned, new mechanics. The huge problem with Median XL is that the multihitting and extremely strong skills make the damage cap a severe issue in the game overall, thus, disabling PvP, regular boss fights, and more. And by this I mean I'll simply delete all Median skills and start on my own.
I plan on become an expert with tiles and mapmaking. By this, all automatic level generations and patterns will be modified by me. Once I am able to import new tilesets that look GOOD (my main priority) I'll also add new tilesets, to make acts more interesting. Acts are too similar and boring. I can add jungle caverns, lava deserts, frozen forests, and way much more.
Item tiers will be re-designed completely. Bye bye boring system of 6 long tiers, this is not full decided yet, but just like there will be probably less items (considering the current useless amounts of items), new item stats will come in manipulating many more aspects of the game. Already bored of being able to tweak your character only with "spel damage" or such things? My intention is to bring many more stats for all aspects of the game to expand customization.
Uberquests: probably the most focused part, as it's the funnier to make. Bunch of uberquest and redesigned charms, charm system currently is rather gamebreaking as they provide too many stats. I can't tell much about this yet as it's something that will be done in the end.