Instead of offering alternatives, I want to offer my congratulations.
Why? Because the game doesn't seem to handle well the case where the party amasses a lot of healing surge triggers (powers that allow people to spend surges for healing).
If your party instead loaded up on those items (robes of contingency, dwarven armor, etc) and each multiclassed into a Leader class, you'd see why you should be thankful that you're in this tightspot.
It's because it's that spot that keeps the game challenging and fun.
A party with enough healing surge triggers can ensure that any one party member can use all his or her surges in one given encounter. There's not enough triggers for this to apply to all characters of course, but one is plenty: this allows the party to recoup from almost any tactical misstep or strategic error, and makes them almost immune to monster focus fire.
From a purely minmaxing perspective, I'm convinced this is a much better way of increasing your party's power than to focus on that extra point of attack or damage bonus.
In essence, it makes it very hard for the DM to properly challenge the party. Without loading so many monsters of so very high level that any challenging fight risks turning into a TPK.
Combined with the fact that no adventurer wants to continue adventuring when out of surges, and how there is no intrinsic disadvantage to taking an extended rest, you'll get chopped up adventuring with fewer encounters that are "just right" on the difficulty scale.
In short, a more dull game.
Feeling vulnerable is something to cherish, and not something to avoid. Sadly, the game rules seems to have a blind spot in this area. So, again, congratulations your players haven't seen this aspect of the rules!