Jax,
The angle for a hyzer flip depends on the disc and how flippy it is -- that's the main reason I use a split-finger grip, because I feel like it gives me a lot more control over the release angle. But for long hyzer-flips, I'd say the release angle varies from about 20* down to as much as 50* depending on how hard I am going to throw it and how worn-in the disc is... though somewhere around 25-30* is probably most common for my worn-in Destroyers and Orcs.
As far as the forehand putt goes, the forehand putt is awesome -- especially a forehand anhyzer putt/approach -- it will open lines you've never seen before. But as for using your left hand to move trees/bushes/branches out of the way, that's a no-no. Check the
PDGA Rulebook on 803.05 "Obstacles and Relief"... the most pertinent part is the first bit, but the rest of it may be helpful to you as well (I'm just going to quote the first part):
A. Obstacles to a Stance or Throwing Motion: Players must choose a stance which results in the least movement of any part of any obstacle except as allowed for casual obstacles by 803.05 C. No relief is granted from park equipment (such as signs, trash cans, picnic tables, etc.) as they are considered part of the course. Once a legal stance is taken, a player may not move an obstacle (or hold it back or bend it) in order to make room for a throwing motion. It is legal for a player's throwing motion to make incidental movement of an obstacle.
B. Obstacles Between the Lie and Hole: A player may not move, alter, bend, break, or hold back any
part of any obstacle, including casual obstacles, between the lie and the hole, with one exception: A player may move obstacles between the lie and the hole that became a factor during the round, such as
spectators, players' equipment, open gates, or branches that fell during the round. Where it is
not known if an obstacle has become a factor during a round, it shall not be moved. It is legal
for a player's throwing motion to make incidental movement of an obstacle.
This rule is frustrating if you follow it as written, and so a lot of players disregard it or bend the rules a bit, especially in casual rounds. This is totally okay if you're not a serious player -- the point is to have fun. But if you're going to ever be playing tournaments, then I encourage you to start playing by this rule. Playing this way will force you to learn to respect bad lies (and hopefully play in such a way as to avoid them) and when you do end up in awful places, it will force you to start using some creative shots and try new throws to salvage your score. You'll also learn when to cut your loses and throw back to the fairway. This is an invaluable part of becoming a seasoned, serious player.
(That said, I'm still learning when to cut my loses -- haven't quite learned when to throw out instead of just trying for glory... its so hard on the ego.)