2 PCs: No Leader

Like the title says, neither Ace nor Al are from a leader class, or even multi-classed as a leader. With barely half of the expected roles covered, I knew I'd have to do something different so that the 2 PCs didn't get creamed every fight.

Anticipated issues:
1. Healing Surges. 4ed is built with the assumption that PCs would have access to some of their healing surges every fight. The way to access the healing that comes from healing surges most commonly comes from powers that Leaders provide, though items, second winds, and the occasional non-leader power will let you heal a bit.

2. Action Economy. For genre purposes, the PCs will need to be outnumbered from time to time. Occasionally they will be VERY outnumbered, and having just 2 PCs will make for some fights that could turn against them quickly. With few/no multi-target/controller powers the fights could turn very nasty, very fast.

These two issues intersect in two places.
Intersection A: Healing Surges, their main access to healing, are boring and use up a standard action when you could/should be doing something to end the fight faster. It's like giving one of the party's precious few actions away, tipping the action economy in favor of the monsters further.

Intersection B: The more they are outnumbered, the more things can swing out of their favor. In my experience, the two things that swing fights back to the PCs are big impressive heals and big impressive buffs: two things provided, primarily, by leaders. Controller dailies are the other thing that can swing fights hard. The PCs don't have access to ANY of this. The one game-changer they do have are Action Points.

My solution:
Houserules:
1. PCs do not gain an action point after an extended rest. PCs gain an action point after each milestone. A milestone is defined as the first encounter of any given day and every other encounter afterwards. PCs also gain an action point when they are first bloodied in an encounter. PCs lose all action points when they take an extended rest.
2. You may spend no more than one action point per round. You MAY spend more than one action point per encounter.
3. You may spend an action point to regain the use of your Second Wind.

This does a few things:
a. With an action point you can second wind AND still make an attack.
b. In a fight where things turn rough (one in which you get bloodied) you have access to extra healing if you choose to get it (by spending an action point).
c. In a tough fight where PCs are outnumbered, they can choose to turn the action economy in their favor a bit, by expending action points.
d. It encourages PCs to go and do some investigation (generally via super secret skill challenges) BEFORE finding heads to bust, so as to go into fights with more Action Points. I don't see this as metagaming on the part of my players. These Action Points now represent the investigators having more information, preparation, and/or conviction that they are onto something important.

If a Warlord ever joined the party, this system would break a bit with all of the shenanigans that warlords can grant on an AP. Also, at Paragon tier, this might get too broken as well, depending on the PC's Paragon Paths. I am not there yet, or even very soon, and my players get that this rule is experimental and subject to tweaking. I am hoping this doesn't make action points seem dull and/or common. They are still a resource that must be earned through perseverance and challenge.

The first fight we had (and only fight that has ended in one side all down) felt about right. Both PCs ended up getting slammed pretty hard by the NPCs early on, and both PCs utilized APs to get back on their feet and take down foes in early rounds, evening the odds. More fights will tell me more, but so far, I like the feel of it.

What am I missing? Do they meet my stated goals? Any suggestions on tweakage?