Doug has a lot more experience at Breck than I do ... I do have the "advantage" of being relegated to the lower mountain this season, which gives me a different perspective than I would normally have!
One amendment to Doug's informative post - there are no greens on peak 7. There are very mellow blues throughout. The runouts just above the Independence lift are suddenly steeper (true blue), which leads to some scrape and bump formation. Peak 7 is intermediate skier heaven.
In my opinion, peak 9 is a better option than peak 8 for greens. Peak 9 has several looooong greens, and they're fairly empty if you go wide rather than going straight under the lift where everyone else goes. On peak 8, you have to either deal with the obnoxious Colorado maze and then ski a blue at the top, or take a slow lift that only takes you partway up for a very short run. Peak 8 is also more crowded (see: obnoxious Colorado maze). However, to be honest, the blue at the top of peak 8 is a pretty "soft" blue - the trick is being able to dodge the people criss crossing under the Vista House.
Also: generally speaking, Breck has a reputation for grade inflation on the lower mountain. However, they seem to have changed the approach for Peak 6 - the blues there would be blacks on the other peaks, and the route to the easiest runs - the run under the lift - is usually pretty scraped, or vis is awful, or both.
Could you elaborate on "better skier"? Are you talking comfortable in all conditions and all terrain, or more of a solid black / sometimes double black skier, or?
As for navigating as a true anything goes skier - I would say it makes a lot of sense to kind of stick to a 3-peak range for the day. I rarely get over to peak 10 (unless it's a powder day and I get to the Falcon before it starts); if I do, I stay there a while and probably won't get to 6 and 7. I get on the mountain at the base of the peak 9, but because of lesson club I often start the day at the Vista House. From there, there are two common routes.
1) Straight to chair 6. In the spring, avoid the actual chair 6 runs in the morning. They're all south-facing and crunch-tastic.
1a) Head directly left - oops - right off the chair. skier's left - , carry speed (eagle eye uphill for people coming down Imperial Face and from T-Bar!), and take the "upper traverse" through some trees. From here, ski the groomer, or cross the groomer and ski B-50 trees to Contest Bowl, or keep going a little farther across and drop in to the close side of Horseshoe Bowl.
1b) Go up Imperial. Ski Whale's Tail (from which too many options to enumerate), or if you're a very strong skier, do the very short hike up Peak 7 and ski Upper Dunes, which will be either fabulous, or terrible sastrugi. There is no middle ground.
2) Depending on how much you're willing to pole, you can get to the T-Bar from either the top or bottom of Vista House. Top is easier. If you're starting from the base of Peak 8, you can take the Rocky lift instead and save yourself some traversing. From the T-Bar, you have many fun options, and you can easily get to the peak 6 and 7 lifts (6 requires a focus on taking every available left and not getting distracted). A frequent lap is 6 chair to imperial to T-bar to 6 chair.
As Doug indicated, this time of the season, being aware of the previous days' temperatures, the current temps, and the aspect of the mountain - these are all key to a good day. Also, shade. In the right temperature range, you may find that the shady side of the slope has snow that's unaffected by the sun. This pretty much requires skiing within one turn of the trees.
