I'd add more straw, enough to cover the newspaper throughout, to give them more traction.
Agree about securing the heat lamp with more than the clamp. If you have a shower rod above, hang a chain from the rod down to the hanging loop of the lamp, that way IF the clamp fails at least it won't fall in and start a fire.
Also you'll need a cover on the tub very soon to keep chicks from popping out. Back when I brooded in a bathtub, I covered it with a rectangle of wire mesh (like hardware cloth) and then taped cardboard around the edges so it wouldn't scratch the tub.
Happy Super Bowl Sunday! Don’t forget thermometer in brooder near heat source on side at chick level. First week 90-95 then wean by 5 degrees every 5-7 days till 65-70 then off. Keep raising to drop temp if do not have something to regulate the light with. They should do fine. Wait till feathered out min 4-5 weeks or 6-8weeks if too cool out to let outside to coop. Hope you have one ready. They grow fast!
