H30 update
If you're taking about the fiberglass cover that you see on some boats just forward of the hatch, I believe you will need to make it yourself. IMHO a sheet of 1/4" plywood (marine or exterior), some fiberglass cloth, epoxy resin and Bondo will get the job done. You cut the plywood into the shape you need and drill small holes along the edges. Remember to give the edges of the closed end (forward end) a sloop angle of about 10 to 15 degrees. This will sloop the sides. You use a stitch and glue method by using small plastic tie straps to hold the pieces together. Bondo the edges inside and out to seal the edges. Then, cut the excess plastic wrap material when the Bondo sets and sand. Cover the seams with fiberglass cloth and seal with epoxy resign. You attach the hatch cover to the coach roof with stainless screws, fair the edges with Bondo, sand and paint. It's about that simple. Notice I said "about." I have used this method to build a dinghy and other projects and it works great. The way you finish the project, the amount of fairing and sanding you do, will determine the way it looks. You can take it to a local boatyard to get a professional finish unless you know how yourself.I cut the nav table on my H30 to level it. We find that we need counter space more than we need a nav table. And, I put our microwave on it. I spread charts on the dining table and keep the instruments in the racks. Other than the main VHF, all electronics can be attached to the pedestal rail. If you don't have one, you might find an inexpensive mount and rail on ebay.Sandwiched into the starboard locker in the head is dead space. Unless you have an A/C unit in there, or you have found it already, it offers some additinal space when a hatch is cut out. It is just above the slot forward of the starboard settee. Next, at the forepeak, there is a little extra space behind the bulkhead. I have seen a small oval (about the size of a football) cut into it. You might gain enough space for shoes, but I don't believe it is worth it.The only other option I have considered is building in shelves and a small cabinet forward of the range. I have seen pictures of someone (not on this site) who sacrificed some of the starboard settee and added extra cabinets. Other than that, you can hang gear nets from the overhead handrails, but you probably know that.Have fun, and fair winds.