>>13927122>>13927171Getting rid of its only weakness, a 4x weakness at that, would be crazy good. It would make Swampert a bit better, especially since the megas do switch around the stats, and could make into a special attacker rather than a physical one, which would also make a good amount of its moves a better for it to have, rather than limiting choice down to the few useable physical moves they have access to.
To be fair, I only say sap sipper because it is the only ability with the effect of making a pokemon immune to grass. Giving it a wholly new ability that would still give it that boost would be even better.