Baby Raising

I discovered today that the Maya Wrap sling works wonderfully as a side baby carrier.  Since the now 20 pound Baby is causing me to get tennis elbow in both arms I am super excited to have remembered that it can be used that way.

Question - How much floor time should I be spending with said Baby Girl?  I have lower back issues, that sitting on the floor exacerbates, but really, is the 20 minutes 3-4 times a day of one on one play I've been doing with her enough?

I also don't think I've been giving her quite enough solids.  It's as much as she will eat at a sitting, but I'm also not following her around with solid food.  Generally about 20 minutes or so after she eats she's ready for a bottle.  Is this normal?  Am I doing something right or wrong or just different?