There aren't any problems associated with using Rage or Rage Gold...I do appreciate the fact that you wanted to use one brand through out but with respect to filler it's not necessary.
Over bare metal, an epoxy primer would be recommended, if your using PPG's DP line, it should be top coated with a 2K primer like K38. The DP epoxies do not sand well at all, but, give excellent rust protection. K38 does have excellent sanding qualities and great hold out. DZ3 is also an unnecessary step.
Do your major body work when the car is stripped (and as many small dents as well), apply your primer...Guide coat, block sand...repair low and high spots...primer block sand...guide coat, block sand, etc...until the car is straight.
Paint companies recommend sealer. I've had this argument many times with paint companies that insist that sealer be used...I ask them 1 question and that question is...When you have a car that requires paint to be blended, why don't they recommend sealer...The answer is that sealer isn't transparent and you couldn't do a proper blend...Then I ask, does the paint and clear still stick?...They say of course it does...then think about it and tell me that I'm right, sealer is not required. Sealer is used so that people can prep a car in a rougher grit of paper, get the job done quicker, seal it to cover the sand scratches and paint. If you prep your car properly sealer is not needed. In my opinion is just another layer of paint material that you can get dirt in while your painting, prep your car properly and save a couple of hundred dollars on material by not buying sealer.
PPG does have other good clears, being from Canada I'm not familiar with all the US part numbers (some are different)...Concept 2021 is and excellent clear as I described earlier. Check out PPG's Global line. They have excellent overall clears as well that do have better sanding qualities than the 2021 Concept a Canadian part # that comes to mind is D894. This clear does polish better than the concept product. I've done several show quality vehicles with it and have been extremely happy. It's your call, either are good clears.
Hope this helps, any more questions? keep them coming.