Change. Increase the odds for the higher magnitudes to make it more consistent and have a chance at being better than Earthquake. Sure it is a gamble but when the odds are really against you, EQ outclasses it so much more so.
keep. it's probably one of, if not the best pivoting move next to u-turn and it actually has a leg up against uturn in that the pokemon coming in would come in much safer with the opponent's stats lowered, perhaps either forcing out the opposing pokemon or providing setup opportunities
delete. it provides no real value whatsoever, i feel. if you wanted to get rid of the opponent's item, that's what knock off is for, and it actually does damage. in addition, magic room is a double-edged sword that works against the user, as well. i can't think of really any situations where it'd be used instead of knock off.
Delete, it's too powerful to be an early game move but not powerful enough to compete with moves like Close Combat, Superpower, and (of course) High Jump Kick. Just give Pokémon like Stantler and Dodrio High Jump Kick instead, they kind of need the extra power.
Round inflicts damage. If another Pokémon uses Round before the user this turn, the user will use Round directly after it (regardless of speed); all but the first Round within a turn will double in power to 120. Pokémon with the AbilitySoundproof are not affected by this move.
Change: Give it the Hyper Voice treatment where it can hit behind substitutes. They are obviously quite rampant in many Doubles format. Additionally, give it a semblance of the Echoed Voice treatment such as a flat BP increase if Round has been used in the turn before. With proper set up, it would be cool to make a team of singing Pokémon that get more powerful the more they repeat the round.