Back linking structure tier 2 and tier 3

I want to push generic keywords to my tier 2 and tier 3 links, do yall have a amount of pages measured where you see results on the money site?

Is it better to use web 2.0s or real domains for this task?

Can I push lighlty on a tiered stack off the tier 1?

Yes, you can use web 2.0s for low traffic volume keywords. They should work as micro niche sites pumping traffic and authority to your money site.

Extra tier pressure mostly gets ignored or flagged now, so less stacking beats more every time.