I started having this problem since 2.0.something (I quit D3 during 1.8 (everything was fine as I recall) and came back 1 week before ROS (loading times got really long). I could probably get a new laptop, but since D3 is the only game that I play and apart from gaming everything works fine I thought I could probably get more RAM (I have 4GB) and replace my HD with SSD. Do you think it would help?
Macbook Pro (2011) long loading screen