My tiny leaky energy inefficient attic scuttle opening needs to be replaced. Ideally, I would like to enlarge the opening as well as install a newer more air-tight better insulated and more attractive door. I know NOTHING about this.

We install wood casing sealed to the ceiling from the inside and outside.

Drywall panel w/ wood backing or 3/4 finished plywood panel w/ a plug of xps foam glued to the panel. We make a fairly tight tolerance of the wood insulation barrier and the xps plug.

EPDM gasket on the casing and screws with trim washers to draw the panel into the weatherstrip through the casing into the panel.

We have used the zippered covers but found those only good for attic stairs. There are some pre made eps hatch covers but I have never tried them.

Battic Door Energy offers a 22x30 attic scuttle called E-Z Hatch. It is a nominal 22x30 size and it is insulated and gasketed to meet Code requirements. Simple to install between existing framing. New Code requires the attic access to be insulated to same level as rest of attic (min R-30).

Make a box out of foam board to put above it in the Attic.