i support the bunny hop mode ( ) but i would say possibly also go for x% faster speed/more gravity, as faster=less control and more gravity is generally harder (both climbing walls and jumping in general), im willing to help with testing if necessary and that is all if any dev is going to even support this gamemode/suggestion entirely.
for a start, from somewhat personal experience i would say 5-15% difference is really minor considering i could finish supermario3 with 50% less speed (to get a point of view try to use the double swords that make you 10% slower to see how minor the difference is)