Good point Chris, and I do the same. I tend to filter out L and T type, and leave the rest. But L and T are good candidates for the reason Chris mentioned.
A couple weeks ago I needed to go from 45% Pioneer to Elite. I ran three trips over the course of three nights, each about 2000 light years out, and then back home to turn in the data.
In case it may help, I flew to the Pelican/ North American nebulas first trip. Toward the Veil East nebula on the second and I cannot remember the third, but it was actually toward the core. I found a heck of a lot of first discoveries going to these places.
First discoveries are so cool, and one of things that attracted me to Elite in the first place. But I feel compelled to add that if rank (which means money) is the goal, then mapping is the key. WW, ELW and AW are great yes. But the bread and butter for me were terraformable HMCs. If you first discover and first map these it's 2+ million per planet. For me that was the path to Elite, as some systems can have four or more of these.