I may not be Morello, but figured I can provide some insight on the Rengar changes for you guys 
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The main point to emphasize is that we're not trying to change Rengar's feel at all. What we do want to change is some of the not so appreciated components of Rengar that make him difficult to balance.
One of these problems is the fact that his Ferocity effects are more powerful based on the rank of the spell. As seen since Rengar's release, builds that capitalize on double casting the ability you're maxing has been problematic (early double Q all-in builds/Tank splitpush double W build). The current solution for this problem is scaling his Ferocity effects with his level across the board (like his heal currently does).
This will make the Ferocity effects equal in power regardless of what you are maxing, allowing you to choose the Ferocity effect that is best suited for the situation you are in instead of being obligated to use whatever spell you have the most points in. This will also allow us to put more power into his base stats and base abilities which should help with his jungle clear.
Another change we're currently looking at is tweaking how his ultimate works. Currently Rengar jumps at you out of no where and it's very hard to react to him because there's not much information being conveyed to the opponent. Now when Rengar activates his ultimate all enemies that Rengar sees will be made aware that he's in the area. What this does is gives the opponent more information so that they can react to the situation.
With this change it allows us to put a lot more power into the ultimate, increasing the duration and speed. While Rengar may lose the ability to jump on an unsuspecting enemy, it enables him to create really cool mind games and toy with his opponents which we've seen from internal testing. On top of that Rengar can get to a location much quicker and stay in stealth much longer retaining the feel of hunting down wounded opponents or scouting an area for priority targets.
Nothing here is set in stone but it's currently the direction we're going, hopefully that helps shed some light on the upcoming Rengar changes.
Edit: While Rengar may lose the ability to jump on an unsuspecting enemy is getting misinterpreted as his leap is being removed from his ultimate. Should have described this in another way :P, he still will keep his leap while the ultimate is active.
