Yep. Adding mass/weight/spring to the valve trains on these motors is about 50 steps in the wrong direction.
There's a reason that NHRA Stock and Super Stock cars use the factory rockers and even the hydraulic roller lifters in Super Stock.
No offense intended to the OP, but it's unfortunate the current market leads customers down some of the paths they choose. Judging by his list of parts and the appearance of some items, your setup is very unhappy. Compare that to the off-road pic & posted......thousands of race miles at higher RPM and more power than yours with the parts I mentioned. You need to sort your stuff in testing so you can get that level of performance for yourself.
My very best suggestion is gather up your stuff & send it to a shop with a Spintron. Something is going to glare......And it'll save you time & money in the long run. I'm sure the cam guys who poke around in here could give you a recommendation who can get you where you need to be. Poof - done. More time to focus on other things.
Vendors: Packages should be made available in the market that include a whole valvetrain system (including valves) plus Spintron data that proves the combination will run clean until 'x' speed. Not hard to do on common platforms like LS, Gen II HEMI, etc. Include test parameters on the data sheet. No reason why a guy like this should ever have to shop the individual bits & hope it all works out.