Draining Steeping Grains

As far as squeezing the bag vs. allowing it to drip, I believe it's question of the tannins in the grain giving some unexpected flavors.

In the batches I've made I have steeped the grains for the maximum time, at the recommended temperature in the recipe, resulting in a darker beer then shows in the literature. I'm sure this changes flavor to some point, but so far not to a negative point IMO.

I use bags too. I have my rinse water ready to go and use the multi dip method of rinsing, like if you are dipping tea bags in a mug. Then, I use a stainless spatchula and a steamer tray from my rinse pot that sorta looks like a shallow collander (stainless), that came with my pot used for rinsing. I put the bag in the steamer and press with the spatchula to drain as much liquid as possible.

You can go both ways on this. You can let it slowly drip out, or you can squeeze (definitely with gloves) as long as a few extra precautions are taken. I would recommend setting a sieve/fine-mesh strainer over your boil kettle to catch any protein matter that comes out of the bag when you squeeze, and be aware that if the pH of your water while doing the mini-mash was too high, you'll wind up squeezing out all the resulting tannin off-flavors from the grains as well.

It is doubtful that the color has to do with squeezing versus not squeezing, although squeezing may have helped. Some factors that play into the color are grain and water quantities (assuming you used the correct amount of grain and water) and the length of the steeping. While the sugar extraction happens very quickly in a mash, the color takes time to develop.