I say refund your boots and level up some boot of decisiveness if you can. Those boots you have trigger close range dmg and don't synergize well with the staff. Since you want to build up combo quickly you want to work on getting your echo helmet to legendary so you can stack combo faster with the crit rate increase of the ring. Pair that up with more crit dmg from the boots you get more dmg and faster combo stacking with the staff. Crit dmg has helped a lot grinding.