I used to feel the same way R, then I realized that it's really not ProVapes fault that 510 threaded atties have such a vast degree of variances. I use the shims to protect my devices as much as get rid of gaps, I like my atties to be snug, so that they won't wobble and cause wear of the threads of both.
The 510 connection was a poor choice for the market to stick with, there is no standard specs for length of connector that exists. A spring loaded center pin is a poor way to make it work, as the spring can introduce resistance into the circuit, and would have greater potential for leakage as well. I think the grommet supported center pin that they decided on was a good compromise, it allows some give, unlike the old fixed pin the slant top devices had, but retains the solid conductivity and leak resistance.
The gap on mine is not between the 510 and the atty. The atties sit flush on the 510 and make a connection (most of them) - the gap is between the beauty ring and the atty. I can make 1/3 of a turn with the ring with an attached atty. Same with other 510s and beauty rings from my flush P3s, when put on the Radius. Thus my theory the thread well is too shallow on the Radius. To quote Provape, "this appears to be within QC tolerance".
R