I wanted to play Champion Toxic Rain (TR) next league start, could you guys take a look and see how I could improve this build?

First time making a build fully from scratch: https://pobb.in/jY9nntpam-hx

I am not really bothered if it's not meta or gets nerfed with patch notes, I just like the tanky play style and it's reasonably fast. Looks like I can get close to 2 million with a decently tanky character with day 4-5 gear.

Would appreciate some feedback on what I could improve. I tried to create a few levelling trees, with cluster and no cluster setups. Also added some very basic post campaign gear, and 2 gem setups (with and without a small mana reservation efficiency cluster).