Nicely installed 600W on a 25'. I'm not sure what panels those are but six Renogy Compact panels would probably fit as well. Its not overkill at all. I believe there's no such thing as too much solar or battery storage. You are going to enjoy the freedom from needing shore power.
2018 Globetrotter 27Q, 36 nights 5,235 miles, 600W Solar - Produced 50 kWh, PD4655L, 6V Batteries, Champion DualFuel, ProPride, 16" tires, 2019 F250 PSD
Sold: 2017 FC25FB, 316 nights 40,150 miles, 400W Solar - Produced 200 kWh in 216 days
2013 Casita SD17 89 nights 16,200 miles