I would get the std pligs back in, the SUper4s are crap and no good at all, especially in the F4R motor which runs on special plugs.
The super4s are conventional nickelalloy whislt the std Ren plugs are precious metal centre electrode.........hence why they are so expensive. but theya re damn good!!
The tickover can abe a little lump and when its cold the car can sit there bouncing a little, but you have to remember the cams are generally of a very high spec as std. They can be comapred to a rally cam as many know it by. The VVT does its best to keep indle and low rpm smooth, but there is pnly so much you can do with cam phasing devices.