For a THS and a challenge league, you're pretty well covered. If you're doing anything more extensive (PBA Regionals, Masters, and US Open type events), you're probably limiting yourself too much.
In those situations, I'm not talking about taking more equipment with you, but to have more to choose from to take with you. I have both the Marvel-S and the Marvel Pearl, and if those were my two most aggressive pieces, I would have needlessly handicapped myself in several tournaments.
I'm not sure why your guy says no asymmetrics. They can provide a different hook shape which is a critical option to have. Otherwise, I like how you're thinking.