Ditto on what Andy said. Those who says you need 3 tons TV for 2-tons trailer have never tried anything else.
I tow 5500 boat with 3900 lb SUV just fine.
Than your impression about safety of motorhome is false. Standard motorhomes are just boxes of wood and cardboard, that collapse flat at any rollover. The only roll-over rated are bus conversions, but those are quite expensive.
Getting new toad is not going to be cheap as well. Think towing bars and axillary brake system.
Motorhomes with children have big advantage. You don't have to make potty stops every couple of hours and wife can bring you cold beverage at 70 mph
Since you are starting your RV adventure and you already own TV, start with a much cheaper trailer and move to motorhome in few years if you really like it.