You could also make just the readying part be once per phase/round. But I agree with the others that say that Gloin is the heart of the issue with the combo, not the Warden. How many times have you really abused the Warden's readying in other contexts? Even with Steward on a Lore hero, it's tough to overly take advantage of.
How do you make exactly the part with readying once per round?