While I get that people using max cape get an advantage, max cape isn't the best in slot and does have it's cons in the form of it having a high general store cost and thus being protected a lot. You do have to do combat for max cape, giving it combat bonuses is something that does make sense, and is something that in my opinion should stay the same. It's not the best in slot for offense, it is for defense, this could be toned down slightly. Combination capes, stat wise, are more unhealthy than max cape is.
>best cape to use when using 2 or more styles AND best in slot for defence
>requires you to max your account
>people who don't want to max their accounts are at an (unfair) disadvantage against people who did
>Vigour
>Best in slot, better than stone if using a special attack weapon
>Has one or multiple items with comparable stats though slight difference in use
>Requires people to play pest control
>People who don't want to play pest control are at an (unfair) disadvantage against people who did
There are things outside of the wilderness that might give you an advantage in PvP, you may consider doing these things as preperation for your fight. Some things may take too long to be worth the advantage, I don't think that that advantage should be changed though. Quest requirements for items, untradable potions and dungeoneering rewards are things we can compare to this; some of these things were incredibly popular in PvP in RS. If it isn't broken OP, it doesn't need to change.
My opinion on max cape: If I work my butt off for a cape, be that a 200m cape or max cape, I would like to be able to show this off pretty much anywhere without having to lose efficiency because of it, be this PvM or PvP. A cosmetic overlay would be a solution to this, for balance reasons it would need an option to turn off in PvP, but since that requires effort it probably won't come. I don't think this needs to be changed at all though. Even if it saves you slots for switches it isn't super significant.
I just don't agree with you on this matter, because how I see it is "I don't want to put as much effort as the other players for a good cape, please change it in my favor."
^