I have played few rounds with uneven lies. As reported it needs some tuning. Indeed, even very slow moving dots (meaning very small fairway slope) have already dramatic effects on the ball trajectory. This looks a bit exagerated.
Not sure it was tested by WGT before releazing it (or perhaps by not so good players among the staff) because I cannot imagine Icon playing it and saying "it's OK guys you can release it as it is now" :) . Perhaps WGT should have some good beta testers...
One suggestion is also to have two views of the box. One as it is now where you see quite well the sidehill slope and another one rotated by 90 degrees to see correctly the downhill/uphill slope. As it is now, it's hard to see the downhill/uphill slope and thus to judge the potential effect on the ball trajectory. Not sure we need numbers to indicate the slope, if the speed of the moving dots is accurate (!), then it's enough.
Concerning tiers, once it's correctly tuned with realistic effects, it should apply to all tiers except perhaps hack and amateur where you cannot stay long before moving up. Otherwise, sanbagging will be terrible! We already see pro with all the top gears, if in addition they play from flat lie, then I don't see any reason for them to tier up. Tiering up should not be a punition.
In summary, I am not against this new feature but I am just afraid by its implementation (this release just show how terrible it can be...). Because it's a crucial ingredient for approach shots (it will thus mostly decide between birdie or par/bogey), it could completely spoil the game if it is not realiable.
We already know that some green mapping are completely wrong (hole 11 on Cabo and many Kiawah greens just to name a few), here the mapping concerns all the fairways, I am doubting that it will be reliable everywhere. This could thus add a significant luck component to the game which couple to high wind could just turn the game into a "hit and hope" game. This must be avoided by all cost.
Regards