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You could do like I did and get an inverter (or inverters that work in parallel) with the option to do "zero output", sometimes called "zero report". That way you can choose to not put power onto the grid if you don't want to. I advise you make the decision now to buy an inverter with that option so that you're not stuck later either putting power onto the grid or using a transfer switch.

When the grid power goes down my inverter transitions smoothly without flickering the lights. Of course, with batteries in my case I have that experience at night too (assuming I had charge in my batteries).

Then there's the possibility that in the future your power utility will have a change of heart on their power buyback plan and make it cost prohibitive for you to participate. If that happens, you'll wish you had the option to turn off the grid output feature without buying a new inverter.

I actually recently applied to put power onto the grid. It turns out that Alabama doesn't have half the regulations that goes with selling power onto the grid that other states have. Plus, I found a loophole in the power purchase agreement where my monthly fee for sell buyback would be fairly small. And I had 811 total hours last year where my batteries were fully charged (in other words, 811 hours in which I could have put power onto the grid). That will obviously increase between now and the end of August when I reach the 1-year anniversary of upgrading the solar system, especially given that I haven't seen the results yet of upgraded solar during spring and summer. So far my data for spring and summer throughput is last year before the upgrade.

But back to making the overall system work well, as far as solar + converting natural gas appliances to electric + EV. Think about how choices like your heat pump impact your grid pull. Some single stage pumps and two-stage heat pumps are very efficient in cooling and heating your home. But a variable speed heat pump can do it with very little power draw (usually) so that at any point in time your overall power load is less liable to exceed your inverter capacity. In other words, don't be satisfied with just getting an efficient heat pump; get one that also integrates well with the power capacity of your inverter. The same with getting a charger for the plug-in hybrid. Get an EVSE (charger) with the option to charge at low speed so that when you charge the hybrid your kW draw from the charger + kW draw from the heat pump + kw draw from water heater, etc. are less liable to exceed the inverter capacity.

With all of these appliances I have the option to run them full speed. I could set my hybrid water heater to heat the water tank like a normal electric water heater and draw 4kW (i.e. if I have family staying for the holidays and need to heat the water faster than when it's just two of us). And I can set my EVSE to charge the EV at full speed if we ran a lot of errands in the morning and drained the EV, with plans to use it a lot later that evening. Likewise my variable speed heat pump will automatically kick into high gear if needed to combat really hot weather or really cold weather ("really cold" for Alabama LOL). So none of the things I'm suggesting about picking appliances with low power efficiencies mean you don't have the option to be practically gluttonous with power when needed. (i.e. I have a hot tup too LOL). I'm just saying if the normal usage from each of them requires little power at any given moment, then there are less times the sum of their power drain exceeded your inverter's capacity. Thus there will be less times you draw power from the grid even on good sunny days. Plus, it means in a grid down situation you're more liable to run your whole house on emergency power from solar.