I think the biggest limitation in our field is the weakness and rarity of organizers.
Jim Drake once said to me that Organizing is a lot like a guild. Thinking about that now I take that to mean the following: Organizers have an apprenticeship (be a key leader, work for an organization, learn to do one on ones, learn about power, learn to identify leadership, and build a base), go forth as a journeyman/woman (learn to agitate leaders, run an issue campaign {not nearly enough supposed masters can actually do this}, be a supervisor, negotiate with a target, manage your own base, develop first rate leaders, learn to raise money), and become a master (maintain and run an organization on a day to day basis, take an organization from recognition fight to Governance, create a new organization from scratch, train and develop a staff from apprentice to journeyman/woman, leave an organization to someone else, and leave well).
I'm sure I missed some key things in my off the top of my head list, but I think that overall this process takes about 5 - 10 years. And at the end of it you may have a master organizer - but that dosen't mean they have digested their experiences in a way that allows them to help anyone else get there.
I think we as a field need to become better about intentionally walking people up this ladder.