I play Guitar Hero on Expert, but depending on which game and song chart (as well as instrument for World Tour onward), Sweet Mercy is it hard/unplayable at times.
Guitar Hero III:
Stuck on Venue Six:
Songs I cannot play:
Black Sunshine
The Metal
Pride and Joy
I typically play Doom on Ultra-Violence, and enable fast monsters.
With the vanilla code, Doom has three difficulty tiers. Yes, I watched decino’s vid on this; one can watch that for more detail, but…
[Easy]
I’m Too Young To Die
Not Too Rough
[Medium]
Hurt Me Plenty
[Hard]
Ultra-Violence
Nightmare
I would go with Nightmare but kinda redundant since I can enable double ammo and respawn monsters in G/L/ZDooM as I wish anyway, and the primary difference between UV and Nightmare is Fast Monsters, Double Ammo and Respawning Monsters anyway, at least this is so in the vanilla code; mods like Brutal Doom alter this significantly (as well as add several extra difficulties of which five of them are for a specific game type).