I don't know, it seems very unnecessary if you get a blink dagger and a force staff. You'd still want a blink regardless due to the cast time on this, and then it's like, do I want a cheaper item that moves me faster and can be used on allies, or a more expensive item that only moves myself. I just don't see much use for the agh now, unless I'm misunderstanding the change and it keeps the damage increase on the ult. Before it was almost never built due to cost and shit, but would see use in very lategame if you could buy it, but now? Even with a damage build it seems shaky with the slow as shit travel time on it. Does look great though lol. Maybe the cooldown would be worth it, like to chase fuckers down and stuff.
Anyway lots of very interesting changes. New items, Echo Sabre seems kinda OP? gives an auto "crit" and a small root every 5secs. Blademail change is HUGE though, especially for supports. Now that it reflect the same damage type, it means a carry can't just turn on his BKB and fuck you in the ass while your useless blademail sits there unused. More cost reduction on common stuff to help supports(TP/flying courier), and ward bounty is huge now, 100g per ward, means investing in a gem or just sentries and going ward hunting can pay off big time.
Hero changes aren't as big, other than nerfing stupid rapier Warden bullshit and nerfing all the common top picks. Enchantress getting a much needed damage nerf on Impetus, Invoker forge spirits getting a pretty big health nerf by switching their health/mana relation on quast/exort as well as a bunch more stuff, OD back to his pre stupid buff arcane orb drain and such. Not too sure if any of the buffs are major enough to make some of the other heroes important. Bloodseeker agh seems pretty good though, having 2 ruptures, but still bloodseeker. I'm not entirely sure what the brewmaster changes result in, but sounds like a pretty good buff especially if enemy team runs away and you end up just pushing a tower with your ulti. Jakiro agh sounds even more broken than it was at a fucking 30secs, but well it's jakiro.