The problem with tees is their stretchiness and where to take them in. Because tee material has quite a bit of stretch and it can be hard to sew especially on the width where it's the stretchiest. With a dress shirt you can simply add darts front and back to narrow the waistand it's a stable material. You can't do that with tees or they wouldn't look right.

Your best bet is to buy tees that are made for athletes and hve quite a bit of stretch. They probably still won't have the form fit you want but it is the best you can do. Ready to wear is made to fit the average figure and not that of a weight lifter

The tee is square. 50" for both chest and waist area. How can that look good with a 34" waist? Where does 16" extra inches of fabric hide? Aww, it just gets tucked in. Am going to try and alter a few tees and see what it looks like.

Sis showed me how to use sewing machine. I did it. Had trouble getting tee over my shoulders. But Shirt looks ok and feels better. I tried a few widths. Is 1-2" of slack around waist ok? Can u tell with 2" of slack or 4"? Loose is loose. Heck, I just went from a 50" width down to 36".

I was going to say just take them in on the sides. I do that all the time. 2 inches of ease is usually considered standard. With stretchy and sleeveless things women often go down to 1 inch. This is probably true of men now a days too. But clearly you need to be able to get the shirt on over your head.
Good for you, btw!
You can do the same thing with your button down shirts. Women would be more likely to add darts at the waist to give some feminine shaping, but I think you could just take in the sides for a ways up from the bottom. Just look for shirts that have simple side seams, not double needle ones.
Good luck and have fun.
Kathy

i tried on a new L tee shirt today at store. too tight in shoulders and arms. waist is fine. i hate snug clothes. but than i used to be 50lbs overweight. i look good and know that snug shirts looks good on a fit person. guess thats why sweaters look good on women.