I think EE's are awesome

They lay a nice colored egg, and most of the time their feathering is quite attractive.
Sex-Links come in two colors - red and black. BSL's are made with a "red" rooster over a "black" hen - most often a RIR or NH roo over BPR. RSLs are a "red" roo over a "white" hen - Again, RIR or NH over RIWs or WPR's. BSL hens will be mostly black with some red highlights - RSLs (or Golden Sex LInks) are mostly red-ish with some white. They are both considered very good egg layers.
Wyandottes are good cold weather birds, and if you could find heritage birds, you'd probably have a good dual purpose hen on your hands. They are not "bad" layers, just not at the volume of those that I listed in a previous post.
Ostrolorp is my way of misspelling Astrolorps -- I find the spell check on this forum to be - lets call it icky - so I don't use it
Your chicks can go outside to play - any time you think it's warm enough. If you are asking - when can they be off heat - then I'd answer - "when they are fully feathered". That's usually around 9-11 weeks. If you are good about weening them off the brooder's heater - you can get them off heat faster than 9 wks.
Yes you can keep chicks in a bath tub. Several here have. WARNING - they are very dusty. They produce a dander that is very fine. You will be shocked at how much dust collects in a short time. One of the things that is very important with chicks is to make sure that they do NOT walk on a slippery surface for the first week. So that bathtup - needs to be lined with cardboard or something (not newspaper - but paper towels are ok)
Just 2 is ok - don't get just one. Also - if your plan is to get 4 - do that now. If you want the details - I'll explain why - but trust me here - you'll have less work if you do the 4 chicks at once and not two now and two later. So - it's better for you to start all 4 at once.
Ok -- next batch of questions please