Lots of questions only you can answer for yourself. Most of it stems from the type of travelling you do & where you do it.
Like the vast majority 5er owners, we get along just fine with a 2KW genny. Most seasons we are on the road for 120-150 days. We dry camp at events like bluegrass festivals, just did 6 days at Albuquerque Balloon Fiesta, without a thought & burn up maybe 5 gal gas a year with the genny. No solar but we do have a decent sized battery bank & an inverter so there is no need for the genny everytime 120AC is needed.
The only time a high powered genny would be nice would be to run the A/C on a hot night. We are seldom at such a place dry camping. In such weather we head for a CG with W/E hookups.
The difference between the price of a 2KW genny & a 3 or even 5KW heavy built in genny buys lots of CG nights, never mind the cost & inconvenience of lugging the beast around.