Remember this is a 2nd level spell so it really doesn't do more than provide a place of safety for up to 8 creatures/people for 1 hour per level.
If you brought the material and had a way to write on something solid then I as a DM would allow you to craft items. Of course you need a light source also. After a while a torch would get smoky in there. Not enough to kill anyone but enough to make everyone cough and gag.
Again as a DM I rule it is about like a field of grass not rock hard but not a pillowtop matress either. Rest is one of the reasons one uses the Rope Trick spell.
It is not lit although I rule it is sufficently "lighted" that you aren't fumbling in the dark, It is more of a "grey" glow that allows you to see in a 3 foot area around you. four other smelly "friends" means just that. It doesn't have an air freshener in there.
Again to read spells you will need a light source but yes, rest, cast heal spells, eat, plan, etc. is well within your rights. I hope this helps as everyone else has chimed in also.