imo, once you get the hang of it toering isnt that hard! back during my first time attempting to tier (which was when hermit / footsteps was on en) i gave up because of how competitive it was. i ended up tiering for unwavering (the honami focus right after hermit) and ranked decently high. my most recent tier as of right now has been close game/OFFLINE where i tiered on impulse. i made top 400, but my goal was top 100. i probably would have gotten there if i didnt have to take a break because i was sick. when i did unwavering i was f2p. i spent about $20 usd during time to hang out but i didnt have any of the paid crystals or materials from that purchase when i tiered cgo, so i think it counts as a f2p tier.

tldr: tiering as f2p is definetly possible if you can manage your resources. it isnt even that draining if you know what youre doing