To echo what Dolomite said, I find a lot of value in Red Dots that have the auto brightness feature.
During SWAT funtimes, I really appreciated it when moving through different lighting environments.
It's not as big of a deal with the Aimpoint because of Aimpoint's single dot, but with EOTech's "circle and dot", it sucks. When seaching a mostly lit building for a suspect using an EOTech and you find yourself moving into a darkened area, you can end up with a giant, unuseable red blob (yes, the weaponlight helps, but it's not always tactically appropriate).
I've always been an Aimpoint guy (still am), but I recently put one of these on my work gun...
http://www.insighttechgear.com/products-mrds.htm
I'm not quite ready to sell my Aimpoint M3 yet, but I'm really digging the MRDS with the armored cover.
As with the Aimpoints, I never turn them off (unless the gun is in the safe) and just replace the batteries when appropriate (Aimpoint = annually / MRDS = bi-annually).
To the OP's post #3, those are really two completely different missions.
The only optic that might meet both of your expectations are the various 1x4 tactical scopes out there.
There's a wide range of price and quality in that catagory.
It seems that the Millett DMS might be a good entry level option for you.
http://www.millettsights.com/scopes/dms/
Personally, I have not seen a cheaper option that is worth owning.
Remember, target shooting is one thing, but if the rifle in question might be pressed into a defensive role, consider it (and what you put on it) a piece of life saving equipment and don't scrimp on cheap crap.