Cant do cosmic horror as my Steve will be too low can’t do variant exploration since my roster is pretty small
Explore Cav EQ every month for a 10% Nexus. The monthly SQ usually has 10% as well even if it's been kind of weird the last few months. If the variants are too tough, I think you should focus on building your roster before pushing for TB. Otherwise you'll end up in a weird place where you have a lot of uncompleted content that rewards way too little resources to be worthwhile doing while simultaneously being stuck at content that requires champions that the uncompleted content would have allowed you to rank up. Even if you manage to push through Act 7, you'll do so with a lot of unfinished content behind you. Progressing at that pace, you'll quickly burn out of content to do. There really isn't that much to do for TBers.