Less than 1 month ago, I paid off my '03 Rubicon. I am now $300 richer each month. Now, I can afford to regear my Rubicon, upgrade the axles, buy 35s, and take the Jeep out!
That said, can you build up your FJ Cruiser to be more durable, with straight axles, 35" tires, and perhaps rent a motorhome when you get the itch to go camping in the National Forests?
I went to a Wrangler Forum meeting a few weeks ago, and the JKs are amazing vehicles - but, not enough to spend $$ on car payments vs. off road trips.