I've been thinking about this. The game isn't really interesting to me until I get a different seed from the starting ones, and also a good starting seed can be the difference between a game winning run and a waste of time. For instance, if I get Thomp in the first biome, I'm almost guaranteed a boss run, regardless of what else shows up.
Why not just let players just pick a non-standard seed to start? Maybe not unlock it right away, like maybe not until you've beat the Forest, or Jungle, or Desert, or Arctic (there are good arguments for any of these). This would let players have a bit more ownership over their own play style, but still maintain the randomness (you only get to pick one) and would let players safely explore how seeds work without feeling like they're wasting their chance at a good run.