IMO; take out the
scrubland, there is no point in having 1 dual and locking yourself in legacy, there are other viable duals, and less expensive.
I would increase soul wardens to 4, the combo with
Ajani's Pridemate if there are 2 or 3 in play is very strong. And considering adding a similar spell such as
Nyx-Fleece Ram which serves as a viable blocker early.
3
Life's Finale seems excessive. How often are you going to need to destroy ALL creatures? I would drop to 1, and SB others if need be.
Finally, if the strategy is to pump the Pridemate until Avatar comes down, i would add some spells that protect them.
Ajani's Presence is solid, or any sort of "protection from" spell.
Hope this helps!