I'd suggest the 17 oz. Embrava brand bottles. You can find them on Amazon - we've found these to be perfect. Lightweight, durable, has a wrist/carry strap, and the way the cap and drinking spout just work very well for a day on the move.
Camelbak hydration bladder - either in a Camelbak or tossed in a regular backpack. Much more flexible than a bottle and you don't need to take it out at security.
We brough Bubba water bottles and they were great for Disney. They're only 16 oz so not super big or heavy. There are no straws or extra pieces so they're easy to wash in a hotel sink. They have a wide opening so you can easily pour in a whole cup of ice water.