My son has a force character, and the set is the way to go if you really want to have a strong forcefield.
Your energy builder, force bolts, has an advantage you can get called force refraction, which has a chance to generate a modest shield on top of everything else. My son says this is up frequently, and provides decent mitigation.
Your slotted passive, personal force field (PFF), generates a protection field that takes damage you would have taken until it drops. Then it regenerates. The damage it can absorb tracks endurance, and the speed at which it replenishes scales with ego. So having high ego and endurance helps.
You supplement your PFF with Field surge, a click power on a 30s recharge. When you tap this, you repair your PFF and improve the amount it can absorb for a short time.
So force defense involves having a sound PFF, with field surge, and energy building with a power that can slap another tiny shield on top. People who say PFF stinks as a passive do not usually have the force energy builder, and therefore rely more on the raw power of PFF to mitigate.
Further helping force is knockback, which effectively slows the damage output of the enemy which spends time in an animation sequence getting up off the ground from your knockback.
The central drawbacks to force are damage. The main damage dealer you get drains out much of your endurance for little damage return.
For these reasons I think going hybrid with another power set for damage makes sense. Elemental attacks have damage which tends to scale with endurance, and the non pet based ego attacks from Telekinisis/Telepathy should go as ego or endurance.
My son really likes flight with his force character, since he can fly across zones taking little damage...by the time something hits you enough to drop the PFF, you have flown past. He says he was able to just sit there and take down +2 master villians with ease by running the energy builder, shield block, and the occasional field surge.
The FOOM attack (cylinder/Force Cascade) is an endurance pig, but it is fun to watch, knocking stuff back in a straight line for a long ways. The deal with getting this to work is to pay attention to your energy builder and when it generates a mini shield. That mini shield counts as an energy form, and when you are under an energy form, force cascade costs a lot less (but it takes off the mini shield).