The problem of a lot of space for red is that it feed into combo. Take for example this:
Remembrance R
Instant
Exile target instant or sorcery from your graveyard. Until the end of turn, you may play that card.
Yes it's a cute card, but the "until end of turn" means it's automatically better in combo because of the decreased cost compared to straight regrowth . At that point the solution is to bind such effects to creatures, so that they can't be abused as well, like the new abbot monk whose pseudo-cantrip is prob less than 1 mana worth. And at that point... you printed snapcaster but it's blue Kappa.
That "fight each other" card as an example of "emotion" for red, can be reduced signifcantly in cost if you word it as a "must attack or block", like this:
Moment of Anger R
Instant
Target creature gain +1+1, trample until EOT, and must attack or block this turn if able.
Making it pump mean that it's not all upside if you cast it on an opponent's creature.
Fight is a perfectly red ability, but extremely underused. I always wanted something like:
Drunken Brawler RR
Creature - Human
As it ETB, fight another creature at your choice.
2/2
That ETB isn't even a strict upside, since if the only other creature down is a Goyf this just kill itself. Something like this would be good only against mana/utility creatures nowadays, and tokens.
if Red is creative, it should also get more modal spells, which aren't exactly its forte.
And finally, give me more cards like Feldon's, that was amazing even if overcosted:
Michelangelo R
Legendary Creature - Human Artist
R,T: create a token copy of target creature. It's an artifact in addition to its types, and has "this can't attack, block, or use an ability with T as a cost".
Sometimes it looks like they breath.
0/2
The idea is that the statues would still have static abilities/activated abilities with no tap cost, and would be usable as fodder for creature/artifact sacrifices.