My opinion on matter:
You have 9 valks, 3 in each squadron. You are talking about things dying quickly but you would only have 3 outflank rolls (you roll for the squadron not the unit inside, they have outflank conferred to them because they are mounted)
You can do 1 command platoon in valk and 2 sep inf platoons of PCS and 3 squads with whatever you want to load them out with.
An all vet list is pretty boring (coming from the guy that plays it alot and really looking to change it) and the inf platoon gives your army the flavor I think you are looking for.