I tried non CP, but it felt like I needed to figure out a different build than the one I normally use.
On PC-NA we have only one 30-day campaign with CP, Trueflame. As a result, this single campaign always has a long queue and high latency during primetime. Curently both Haderus (7-day with CP) and Azura's Star (30-day, no CP) rarely have any queue and I've experienced generally higher frame rate, smoother performance, low ping on these other campaigns.
Certainly seems most players are not interested in 7-day campaign, not sure whether this is due to the greater rewards of 30-day or what, but if Haderus (the 7-day) were increased to 30 days, I feel we would see an evening out of the population between the two 30-day campaigns and generally more enjoyable experience.
As it stands I either avoid Cyrodiil during primetime or go to Imperial City, which has generally low latency and higher frame rate on low end PC compared to the rest of Cyrodiil.
I play them all on different toons. Azura has the best performance but the worst population. TF has the most people and the most lag. Haderus seems just right when it's 3 bars across for everyone. BWB was fun but imbalanced. A lot of level 45-49 camp at that level.