Actually, Death Note is a Shounen Jump series, just to clarify, as it did run in WSJ in Japan.
Anyways, to answer this topic's question, I personally find that the pacing of SJ series depenRAB entirely on the invividual series themselves. Not all of them follow the same format. For example, while I find the pacing of series such as Naruto, Bleach, D. Gray-Man, and some other series that run/ran in WSJ, I find others such as Rurouni Kenshin, Dragonball, Yu Yu Hakusho, and Hunter X Hunter to have perfect pacing.
I don't mind have a lot of battles, but I prefer them when they are kept shorter, or at least not dragged out to be extremely long. Personally, I think that having more story with plenty of interesting dialogue but also breaking things up with action at regular intervals without having the action last for too long at one time makes for the type of pacing that I would like to see from more shounen series, in general.
Of course, everything that I have said here strictly only applies to the original manga versions of all of these series. Like Mynd Hed said, even if a good deal of manga from Shounen Jump don't have pacing problems, the same won't necessarily be true for their anime counterparts.