All sounds perfectly normal to me
They have two different kinds of poops - one type they eat sometimes (they have two stomachs and can redigest nutrients from these poops which is normal). The edible type are usually hard and black. A softer poop is ok. You only really want to worry if there is liquid diarrhoea.
Daily veg is fine. Initially every 3 days or so but after a week or two they do well to have it every day. But just a tiny piece - about 1cm cubed size for a syrian and a bit smaller for a dwarf hamster.
Natural treats are best - like pumpkin seeds or half a shelled walnut eg.