Well I'm not too sure how I feel about this dataslate, I'm not gonna lie. That said I seriously lack in experience with V9 and different army so take everything I say with a grain of salt.
As a tau/eldar/necron player, well not sure how I feel about it all. I feel frustrated some things got nerfed yet I feel relieved the army I'm going to field are not going to be nearly as broken as they used to without having to try to make a broken list.
I understand the minus to hit for ignore line of sight rules. That make sens to me, because most army might have a way to mitigate that problem. But the minus to AP... not gonna lie I feels it's truly undeserved. I understand out of line of sight shooting was too strong and needed to be toned down a peg or two, but it feels like point increase in the right spot would have been enough to improve/solve part of the problem.
Tau got hit pretty hard but they deserved it, at least some things really where busted and the core change on the broadside as much as it pains me to admit it was deserved. I just feel like just the nerf to indirect weapons smacked them down a fair bit already and might and other nerf on top of that might be overkill. Montka nerf though? Make sens to me, it was broken, even though I regret I did not have the time to play one game with it before it got nerfed. XD
I feel like eldar though have slipped under the radar of GW because Harlequins where THAT insane. I do feel like Eldars are, not by much, nearly as nasty as the harlequins they have just been over shadowed.
Oh and bodyguard rule change? Thanks go that is good, because that rule was damn stupid in my opinion.
So yeah, mixed feeling so far.
Overall though, it looks pretty good. I feel like it's going to be fun to play against different armies hand have some fun
PS : But GW can we please stop escalating the rules? We have rules within rules that rules the rules, ruling over the game?