We have a small Casita Camper and camp primarily in Forest Service or National Park campgrounds. Our electrical use sounds very similar to OP. I initially installed a 50 watt panel on the camper roof to keep our 88 ah battery charged. We spent 2 months during the summer in the western part of the US and found we were able to keep the battery fully charged almost every day. Did not need 110 volt at any time and was able to keep charge levels always above 60%. The convenience of leaving it on all the time and not being concerned with getting it out, positioning it, and theft is a huge plus in the way we use it.
We did find in the east because of shade and lower sun angles later in the year along with more rainy days we could not always get back to 100% charge. I bought a portable 100 watt panel for which is very beneficial in chasing the sun in marginal conditions. We still prefer the fixed roof mounted for the convenience and only use the portable panel on the occasions we loose ground because of difficult sun conditions.
My vote is to do both which is the best of both worlds.
