I don't necessarily play but here are my thought on these ones:
Attack - Maybe instead of negates Warrior's guild tokens. Maybe they can get x2 or x3 tokens for each kills. (If it's how you normally get tokens.)
Defence - I like this idea as it's the same as old-school, but with how fast you can get to boss any everything maybe add like a 3 minute cool-down when activated.
Magic - Good idea, don't know about including the wilderness though, and maybe add it to where you can use this while in combat.
Slayer - If the player chooses to repeat task, they will only receive 70-75% of normal slayer points.
Strength - Add an activation with this; When you equip strength cape player must right-click "activate" to get super strength bonus.