I was reluctant to say much since I know you're competing right now, but I do think this will help you fix a few problems at once. I think you are fundamentally leaving much of the potential power out of your core/weight shift/oblique slings on the table lacking side bend in any case.*
1.
Nose over toes: Yes. Don't take the head
too far. Could be that more "nose over toes" makes you do it automatically in transition, maybe not. Worth a try. Play with it in the drills too with the throwing shoulder backswinging lower than the off arm shoulder.
2. Front hip clear: yes.**
*
Practical point: I'm reluctant to give you this advice because I know you've been competing meanwhile, and trying to throw discs straighter and flatter. Notice that if you try to fix this, you are probably going to have trouble with your "straight" angles at first if you commit to this change because it changes the throw axis. All of those pros I picked above were throwing somewhere close to 'straight and flat,' so you can see the side bend is a feature and not a bug. They do tend to have somewhere between 10-20 deg. hyzer depending on the shot power and rely on a bit of flip. On power shots you would be able to pursue your "straight" shots with your -1 turn discs and just change the disc speed. So if you don't like it in the short run and put more value competing, you might back off of it. But I think you're going to have a power limit if you don't fix it in the long run.
**
Theoretical + practical point for learning posture & sequence: I've been looking at this a lot again relative to the front hip clear after talking to a couple more coaches. Wiggins' front hip is already starting to power the shot as his foot is hitting the ground. He's got some athletic resistance in that leg as he lands from the toe up, which is exactly synced with his move out of the backswing. It's beautiful. Notice that despite all that force he's bringing in the action is smooth because of how well postured he is. This is one benefit of being athletically balanced in general:
McBeth's form emphasizes a bit more hip/shoulder separation than Wiggins', which some coaches think might be less efficient and harder on the body if you take it too far. Notice in McBeth's move, he doesn't really seem to start exiting the backswing until after his leading heel is all the way in the "crush", whereas Wiggins' sequence begins exiting the backswing slightly earlier. But fundamentally they are both getting insane ground contact+"posting up" into the front hip clear to lead the swing. I like this angle because you can see why McBeth calls his distance drives "violent" on the body. Watch how much impact and clear his front hip gets, even pushing him "up" hard against the ground. It's possibly "better" to be closer to Wiggins' move from an efficiency perspective, but educational to learn from both and tinker a bit what fits to your body. If you watch McBeth over the years it's clear he has played around with this too.
In any case you want to fish around in this space because you still need those oblique slings in the game, which requires some (1) side bend and some leverage for the backswing against the rear leg while shifting forward and (2) getting that sweet ground leverage in posture. FWIW my longest drives are when I connect those two things at this point.