the early bird gets no sleep

I need some advice.
My kids have always been early risers. Sawyer is actually worse than Savannah and I didn't think that was possible.
A little background for you...
Their average bedtime is 7:30. That's pretty much been the bedtime since they were each under 6 months old. And they've both always been up and at 'em by around 7AM. The 7AM really has no correlation to the bedtime. If they go to bed at 6:30, they still get up at 7. If they go to bed at 9:30, they still get up at 7. Actually a later bedtime usually makes for an earlier morning time. The saying Sleep begets sleep? If you every need to test that out, take my kids.
Anyway, for the past year it seems the 7AM wake up time doesn't please Sawyer much. It seems he prefers 6AM actually. Sure, there's the random morning he'll sleep till 7... but usually I can count on him being awake by at least 6:30. And there are always a handful of mornings like this morning... 5:30.

Unless I'm mistaken, I think I remember Savannah going through the same early morning thing about the same age, just before or around the time she turned two. With her, we implemented a simple solution...
She had a ladybug lamp (one of those cool soft glow lamps that is a glass globe with an inside shade that spins from the heat of the lightbulb, projecting pictures on the wall) and she was in love with this lamp. After many many early mornings of directing her back to her bed, I decided to put those ladybugs dancing on her wall to work. I plugged the lamp into timer, set to turn on and off at her bed and naptimes. I explained to Savannah that when the light was off, the ladybugs were sleeping and we talked about when they were sleeping, she should be sleeping too, so she needed to be quiet and in her bed. At night we said goodnight to the ladybugs before they "went to sleep" and in the morning, she was to stay in bed quietly until they "woke up" at 7 o'clock. That was her signal that it was morning and she could come and get us.
She loved it and it actually worked like a charm. (Until she eventually figured out how to turn the timer on and off, but that's another story.) She still of course, was waking up at 6 or 6:30, but she would stay quietly in her room waiting for her ladybugs. I think staring at the lamp, waiting for them to "wake up" put her back to sleep quite often. And after she got into the habit of staying in bed until 7, she was actually sleeping until then more often than not. And the great thing about the lamp, was that it was a soft enough glow that it wouldn't wake her up if she was still asleep when it came on.
It was great while it lasted. And then I broke the lamp moving things in the bedroom one day. After that, she learned to read a digital clock, so she just used that, knowing she could get up at 7.

But Sawyer. He's awake at sometimes 5:30. And then, since we've still been sticking to the 'it's not time to get up until 7' rule, he's popping in and out of his room for sometimes an hour and a half. He'll come out into the hall (he has a squeaky door) or into our room, and all I have to say is "back in bed Sawyer" and he'll go... but then he'll be out again two minutes later. I wait until 6:30 and then I tell him he can turn on his light and read books. But he still comes out after what appears to be enough time to look at one book. I've tried going in and piling him up with books so he'll at least stay for five minutes at a time, but it gets old. I've laid down with him, trying to get him back to sleep, I've tried just letting him play in there.
But he's disruptive; He slams the door after the first 5 redirections back in his room, and sometimes he even sneaks into Savannah's room to wake her up.
I find myself thinking we're all awake, we might as well get up... but I don't want to!! I don't want getting up for the day at 6AM to be the habit around here. Even if the kids are awake in their rooms, I just want to lay in bed til 7.
Ryan for months has been saying, "why don't you do the lamp thing with Sawyer like with Savannah? (like it's up to me! um, aren't you just as capable of finding a lamp and trying it out yourself?) She was this age." And yes its true Sawyer's the same age, but he's a totally different kid. I just don't think he'll get it, and even if he does, I don't think he'll care. I just don't see it working for him. That, and the fact that he still has the horrible habit of unplugging anything he sees plugged in in his bedroom, so even if I put a lamp in there, it wouldn't stay for long. I can't even keep a nightlight in there. Hey, do they have outlet safety lock things that keep it locked with things plugged in?

So now Savannah's back in this early habit too. She can read a clock and knows she can't get up until 7 o'clock, but for instance, this morning I found her in her room with the lights on, fully dressed and writing at her desk before 6AM. Part of me says, oh well, as long as she's quiet and in her room, she can get up whenever she wants. But then again, I know she's still tired, and I know we'll all be paying for it later in the day, and I don't want this early rising to be an unnecessary habit. I'm afraid that if I let them get up at 6, when really they could use more sleep, it'll just be a habit that creates a sleep shortage.
I think it's partly a control issue for me as well. I want them to sleep when I want them to sleep!!
Part of me wants to just say forget it, their biological clock is just programmed to get up early, get used to it. But like I said, I just don't want to give in to that yet. I feel like even if they're awake in the 6 o'clock hour every day, we shouldn't all have to be at full speed awake until 7.

Anyway. Any ideas? Thoughts? Advice?
Am I stuck getting up at 6am every day? Should I let them get up? Should I train them to stay in their rooms quietly until the appointed time and hope that some of the time they decide to get more sleep? If so, any ideas on how to do that with a two year old? I know you all have some creative ideas, so hand them out!

***Just to add...

• Ryan is up and out the door for work by 6:30, so really it's just me resisting the early mornings. And it's not him being up that wakes the kids.
  
• I've tried just leaving out a snack and the tv turned to kid shows and letting them go downstairs when they get up early... Sawyer just gets into too much trouble by himself.
  
• We have played with bedtimes with Sawyer (slowly and over time), and he did seem to do better in the mornings for awhile if we kept him up till 8 at night. For awhile. Then he slowly went back to early mornings and then he started cutting his naps super short, so we went back to early/normal bedtime, because he was short on sleep all around.
  
• He naps an average of 2 hours at noon every day.