Do my seedlings look healthy?

Look fine..........don't over think things..........they will need potting up ASAP though.

Yes, and even if you see blemishes on the first 2-3 sets of leaves, it is not always representative of future growth. inconsistent pigmentation and such on first sets of leaves isn't too unusual. If you have a good formula for a soilles medium, then it's virtually impossible to have problems. Stick to religious 10% runoff.. adjust formula as needed and 90-95% of plants can pull off same reservoir without fail.