Here's our experience, for what it is worth.
1.Our galley is less than 6 square feet, yet we regularly serve 6-8 covers at a time.
We have even done a well recieved thanksgiving dinner. Eating on a boat buys you a whole ton of forgiveness from otherwise picky guests.
2. We don't buy anything from a chandlery. go to your nearest dollar store and buy melamine plates, and non-skid placemats, and a packaged set of flatware. for $20, you should be able to get a dinner service for 6-8, and while it aint;' fancy, the atmosphere more than makes up for it. For a further $75, you can even get a usable set of nesting cookware from any number of online retailers. So, for under $120, you can have a fully outfitted galley, including cheap but serviceable stemware, for those picky guests who don't like to drink their pinot out of solo cups.
(not that there is a difference between "guest" and "crew'- crew will happily drink whatever you have out of whatever you got, while guests are more high maintenance. in other words, crew get invited back, guests get a one-time pass.)
3. Get a crapload of 1/2 pint and 1 pint sealable reusable containers. You will always dice too many onions, too many peppers, too much garlic, etc., save it and reuse, or, if you have the time and forethought to prep, dice extra for meals the next day.
4. We don't use a pressure cooker. we don;t have room for it. if you've got room go for it.
5. Non-pressure alcohol stoves will cook damn near anything, no matter what anyone says. We have used ours for 5 seasons, and have used our PITA Kuuuma BBQ twice.
The key is to keep the alcohol burners topped up- fuel is heat, and heat is your friend. Light the burner, lay on the pan, then let the pan get hot. Go chop cilantro, or more garlic. You can always turn the heat down, but it is damn hard to coax a full pan to get hotter. And nothing has ever been ruined by more cilantro or garlic. except a vamp[re's grand entrance. and dessert.
Filet mignon and asparagus risotto on an alcohol stove? Done it
Pork souvlaki with pan-toasted vietnamese style baguette, fried peppers and onions, tzatziki and hummus? done it.
6. Spices are like sex toys- try 'em you'll like 'em! experiment, have fun, with tarragon, cumin, thyme, rosemary, oregano,, keep a bunch on board. Hell, with the right spice profile, a pouch of ramen noodles and slices of fried bologna in boiling water will make guests swoon.
7. Worcestershire, Siracha sauce, Soya sauce, tabasco, hoisin sauce, maple syrup, oyster sauce, extra virgin olive oil balsamic vinegar and a bottle of yellow mustard don't take up much space but can make damn near any damn sauce or marinade you may require.
8. get at least three pairs of tongs.
9. all of those keychain floaties you get at boat shows? attach them to your tongs. trust me.
10. The money you have saved on flatware, dinnerware, expensive pots and pans, spend on a good set of knives.