I have been researching as much as I can on these two types of kits and I thought I had it figured out. However, the more I research, the more I get confused. I don't have a lot of time to sit in front of the computer, so i hope y'all can help get directly to the situation at hand.
I want to add some height to the front, not necessarily to the back. I plan on adding bags to the back for towing and that is why I really don't want to dive in raising the back. I want to be able to keep some rake and a nice stockish ride. So, I am thinking of getting "D" rated 33" BFG KO2's and a 1.5" AutoSpring or go big with the Boss Coilovers. I would like to go to 34's but that jumps it up to a 10ply "E" rated tire.
I read today that both options are bad for the truck front suspension geometry, but I could have sworn by going with the Boss kit eliminated that as I thought it was a real lift and not a level.
I read some bad things on the Tube of how adding 2" level kits have wrecked havoc on their joints.

 

Coilovers do not eliminate any of the CV, ball joint angles. Coil overs are just different springs(and shocks) which you can adjust the spring rate to raise the truck to desired inches. The higher you go the stiffer the ride. A 2" spacer and a 2" coilover would have the exact angles. These spacers have been around since 2004 when it was the "new" f150. Been millions 2" spacers installed, minimal troubles. A spacer will keep the original factory ride.

 

What he said ^^

 

See, this is where I get confused, or better yet, being misinformed. I called a popular dealer of these items today and they told me that a leveling kit will make my truck ride much harsher over the Boss Coil overs.

 

I had auto spring 2" spacer on my 07 for basically the whole time I owned it (so 8yrs) the ride quality was as good as stock, and never once has an issue with anything that would have been linked to that. From what I've read and heard anything from a 2.5" and up puts the cv joints at a pretty good angle which can cause future issues as well as the upper control arms. The only way to get around this would be to do a true lift for anything above 2.5". I can't speak for coil overs as far as ride or performance as have never had them. I will however be getting these for this truck. I'm looking at getting the Billstien 5100 ride adjustment shocks when they are released as long as my patience holds out lol

 

D and E rated tires will definitely affect the ride quality

 

I had a 2wd 2004 and put 4wd rancho readylift coilovers on it and a 2in block in the rear so I could fit 35s. The ride was certainly stiffer and I would say very rough. Going from 2wd stock coils to a 4wd 2in lift coilovers netted about 3.5in of front lift. Being 2wd I had no cvs to worry about but the uca were definitely at a sharper angle and ruined my ball joints. dont go over 2.5 its not worth it. I did a 2in on my new '15 and will be running 285/65/20 with intent to get coilovers later just for a firmer ride and better handling offroad. If you just wanna get bigger tires or better stance and dont plan on doing moderate off-roading just get a level.