I sort of understand your point here. However on loading into the game I cannot actually see these changes in the challenge menu. I am in your situation and have been playing since launch. I never believed the ranking XP needed adjusting. The weapon XP/progression did and still does feel excessively long for me. I know it's dependent on how you play but if it takes 50 plus hours to master one weapon, that's too long imo. I am 150 hours in nd maybe have one LMG at lvl 30 before I switched to another for a chalenge. I have spread my time across all classes so it's hard to be accurate on time frame but it feels like a lot.
Some challenges are also an actual joke. A score of 10,000 in one match of king of the hill? That's just one example of ridiculous from the top of my head. The other thing is, I would like them to fix certain challenges that just aren't described correctly. My example, "get kills with different types of weapons in a match 0/15". The challenge is actually to get 15 long range kills in a match. How can we complete challenges that aren't explained properly in the first instance? I'm sure there are more but that's my take.
I appreciate the game, I appreciate the players. I also appreciate some of the efforts from the devs but I do wish they would fix what is already broken. They have our money already so now, it's concentrate on the free side and cashgrab with microtransactions. We'll just take a backseat unfortunately.