Bad things about riding on interstates..
Illegal everywhere east of Texas...
Shoulders on interstates are full of debris... nails, glass etc
Traffic is always zooming by you at 70-80mph
If they are doing construction on a bridge and the shoulder disappears, you're screwed.
If they are doing construction using jersey walls with no shoulder, you're screwed.
Exit ramps are a pain... either you risk getting yourself killed by cutting across them or have to climb up them and down them again each and everytime.
So basically, yes, it's 100 times wiser not to use the interstate.
IN a few areas like trying to do the Route 66 thing in the west, you have no choice but to use the interstate. But I would avoid them at all cost.