I guess replacing a 90 with two 45's isn't technical a change, but there must be a lower probability of a clog with a 45 instead of a 90. Or is it a waste of time??
Looks Good
I'll put a Wye in for that cleanout on the vent once I get one.
Not really needed. You can clean a drain through the 2" p-trap
This where the 2" shower drain joins 1.5" vanity. If using two 45's instead of one 90 results in a high flow velocity, then I'll put in two's 45's where it turns into and down the stack.
Leave the 90 and Wye as they where because you had to add another 45 fronm the sink
Here's the vanity with different config. I hope that's what you meant for the Wye at the cleanout.
Yes