Bought new TT today, 2016 Stealth, worried I cant pull it!

If your rear is not sagging much, you might consider the lower StableLoad wedges for your F150 rather than bags. It will take the bounciness out of your ride more than bags. Heavier dampening shocks will also help with bounciness.

Prior to spending money, you can try tilting your hitch head back more to get greater preload on the spring bars...