You won’t be missing anything.
For giggles, I actually played a bunch of my technomancer by turning off all the interface elements, setting the world tier to 1, and just playing it like a goofy shooter. No minimap, no ammo counter, no cooldown timers, no hit point bars or status icons. Just a bunch of over-the-top gunplay and spell powers.
This was also a great way to learn the AI behaviors of the different enemies.
Well, it’s called “normal” for a reason! It’s not like the difficulty doesn’t scale when everything is the same level as you. It’s a perfectly viable way to get through to the expeditions. And really, there’s no reason to push world tier because all you’re doing is chasing loot you’re not even going to keep. It’s all going to get rendered down into components. Basically, you’re stocking up on scrap, shards, and your mod collection, and you’re going to earn this stuff regardless of world tier.
As I think @stusser said upthread, there’s no point turning everything into a bullet sponge that takes a long time to kill. It’s all about setting a reasonable TTK while you get to the level cap, at which point a whole other endgame system takes over for the expeditions.
That said, pushing world tier up is a really cool way to play the game as well. I’ve really enjoyed it, but I’m glad I didn’t let it get in the way of seeing what Outriders has to offer in the end. Ultimately, I think Outriders is about the expeditions. The storyline, side quests, and 30 character levels are just the way you get you there.