can the targeting be improved?

Hi to everyne (i'm sorry for my bad english), i played the stress test the last weekend, everything is awesome the only bad thing that i found is the targeting system i mean, i played a lot of games and a lot of arpg (or hack'n slash) and in every games when i target an enemy and i'll click on it my char move toward him and start the attack on the second click, in path of exile, instead, when i found an enemy and i put the mouse on him, in the first time appear the health and the red boundary around him and when i click there my char move toward him and (following the enemy with my mouse) i'll lose the target and i spend a lot of time to re-acquire the target to start the attack and i need to stand until th enemy come to me for a good targeting.

i thought that was a latency problem or an fps problem, but also when i have 60 ms of latency and around 40 fps the problem appeared again, every time...

i found another one problem, on some of enemies spell cast (don't remember the right spells but were only 2 one of them was the spell like "frostbolt" with the support gem of multiple projectile, even an enemy spell not mine, appeared versus the medusa boss at the end of the first act) other then the normal effect of the spell, on the ground also appear an invalide texture, two to be precise are the ones I've seen, the first was a kind of a water green cone, not a perfect cone but almost, the second was a purple rectangle, the dimensions were exactly the range of those spells...

lastly i have a question (donno if this is the right section of the forum) because i did not understand on the site, i know that the pvp is not ready to be tested but i want to know if in a future (or on the last version of the game) the pvp will be available only via leagues (if i understood correctly), accordingly only an open world pvp, or will be available also in other terms like for example in other leagues, or in istanced areas (like arenas for example), or in dedicated tournaments and so on...

thank for your interest and answers ^^