Yacht club restricts members to one electrical outlet.

Larger house battery and inverters
we draw about 10>14 sitting at the dock and highs of 120 amps when dryer hot water and stove on( it think I have seen it draw more but not often)
on dock
Set inverters to only take 30 amp max (or what ever they have available )and voltage high and low cut off ( we usually set up a 50 amp but can live on 30 and in a pinch have done 15 )
You make up lost ground during non peak times like over night
Now his will not help you if are constantly over the 30

Not cheap but it gives you the protection on voltage swings and trips down a wet frozen dock in the middle of the night to reset breakers

At anchor
a great setup in a quiet bay being able to run everything for a day and only firing up the genny for a couple of hours during dinner

It's hard to answer your question without knowing what shore power system your boat uses and whether or not you have any 220v appliances on board like air cons, cook top, oven etc.

Most boats between 35' and 60' usually use a single 120/240-50 amp cord, give or take a few feet. If you are at a marina with sub standard service, you may have just 2 120-30 outlets to plug in using a smart Y adapter. If that's the case, you can't do much as both legs must be available for power to flow

I you have a boat with two 120-30 cords then you are unlikely to have 220 appliances and can connect just one cord, although only half your systems will be powered.

In this case, one work around would be to have both sides of the panel connected together, with a rotary switch or a pair of breaker with safety slide so you can power both legs off a single shore power cord AS LONG AS YOU MANAGE THE LOADS AND NOT RUN MORE THAN 30 amps at the same time.

Sometimes marinas are willing to re wire your pedestal to provide enough juice, although usually at your cost. If they are not, finding another marina with proper electrical service is probably your best bet.

As to running the generator when cooking and drawing a lot of power, it is an option although it is likely to be frowned upon by your neighbors and the marina. If your boat is
Gas powered, I woud not even consider it because of carbon monoxide risks to you AND your neighbors.

An inverter isn't going to help much since cooking and air con pull way to much power

Can you recommend a cure for crabby, old boat captains?

If you decide to calculate the load your boat draws, figure 125 % of the largest motor current plus 100 % of anyting else you think you'll run at the same time.
The 125 % factor would overcome the inrush or " higher starting current" as stated above.
AC is prolly the biggest draw with the biggest motor > 125 %
Cook top, water heater, TV, > 100 %
This is calculated load.

Some boats have an ammeter built into the power center that would also give you an idea of your actual load.
You could manage your load by running around shutting things off, like the hot water heater while using the cook top, but that is a pain. One cold shower and thats the end of that....

Still it would be helpful to know the power available at your slip.
A single 30 A 125 V. or a single 50 A 125/250 V and how that pedestal or outlet is fed from the source.

A rocking deck below 2 solid feet.