To me that's only a problem with the older and younger actors. An actor who was in their mid 70's during BB and now they're in their 80's trying to play someone in their late 50's would look weird. It's even worse with a character like Jesse who was just out of H.S. in BB and would be an actor pushing 40 trying to play a 12 year old character, totally unbelievable.
If the time frame was when character was in their mid thirties to mid fifties and the actor is in that range, I can easily suspend my disbelief.
He's not ready yet to take over the territory. He want's to hurt his rival, not take them out yet. Take it over slowly and carefully. Sneakers don't rot away in a few months hanging on wires in a hot and dry climate. It was a few years before Gus took over the territory completely.
Also, Hector is just the tip of the iceberg that is the Sinaloa Cartel. If Gus were to take him out, he'd reap the whirlwind.
