There's a good reddit thread going on with the suggestion that weekly challenges shouldn't expire during the course of the season. Dole out those challenges on a weekly basis, but at least let people catch up to a challenge they either didn't have time for or couldn't do.
I think the "Daily" system can be left in as is, expiring after three days, but as is, someone who has to miss out on a week's worth of challenges for life reasons (vacation, work, whatever) is going to come away feeling uncertain about how far they can progress (despite the promises of 65% completion to get to rank 30).
I do think that the Elite challenges should be difficult, but as implemented there's a little inconsistency in it -- I'm not sure killing 100 Eximus Enemies is really that elite, it's just a time consuming thing that happens as you play. The friend/clan requirements are a cool idea to try and encourage people to play nice with others, but it's such an easy system to game by becoming friends for the sole purpose of getting the challenge done and then never talking to or playing with that person again, but it also puts the onus on people to bother doing all that if really want they want to do is just play in their own little bubble.
Another idea is you could let people pick their challenges -- almost like the daily tribute system when you get multiple logins. On the first login of the weekly reset, present a variety of challenges to people and let them choose the ones that suit how they like to play. Do it in tiers so they have to pick a specific quantity in each tier so everyone is able to earn the same weekly standing, but at least they can look at that and go "you know what, I'm not doing a 60 minute run anywhere, I'll take the (hypothetical) 'Complete A Level 30+ Capture in Under 2 Minutes Solo' challenge).
Finally, in terms of the rewards, I would suggest taking wolf cred packs out of the standing ranks and instead dole them out with each rank as you progress. It's 300 wolf cred in total, so every time you rank up you get 10 wolf cred. (I'm assuming a system like this is already in place for the prestige levels.) Obviously that would mean replacing those rank rewards with something else, but it would really help feel like you're actually earning something with each rank in terms of the wolf cred store -- and I think making that feel more valuable is going to be extremely important to the success of this, as it's the one reward type that people have some agency over.