That many conductors is fine - you have no issues with that. Your load ratings on that box are important. You are reworking it - so it will need to be in code.
EDIT 5-15-2016 Something else that might be helpful a box fill calculator
PDF Link for a nice short quick reference.
The following paragraphs of text Were taken from here >
The 2008 revision of the NEC significantly changed 314.27. Significant changes often bring numerous errors. The 2011 revision corrects an error in the previous NEC by requiring that boxes installed in a wall for luminaire support must be marked on the interior of the box to indicate the weight ratings of the box. The 2011 revision also: breaks up the requirements into a list format, for easier reading; incorporates the provisions for lampholders into the title of the rule; and revises the luminaire box ratings for clarity and ease of reading.
Ceiling Fan Boxes
Outlet boxes used as the sole support of a ceiling-suspended (paddle) fan must be listed and marked as suitable for this purpose. If the maximum weight isn’t marked on the box, it is allowed to support a fan up to 35 lb. If the box is marked with a weight, it can support a fan up to that weight, but not more than 70 lb. Ceiling paddle fans more than 70 lb must be supported independently of the outlet box [314.27(C)].
Occasionally, an electrician may install an extra unused switched conductor in a luminaire outlet box installed in the ceiling. While this may seem like a nice feature — because it allows for a future ceiling fan — it’s a Code violation when the ceiling fan is finally installed, unless the box is listed to support a ceiling fan. This change was accepted after initial reluctance, because the NEC isn’t in the habit of dealing with future violations, no matter how likely they might be.
The result of this change in 314.27(C) is that such an installation must incorporate a box that’s suitable for ceiling fan support, despite the fact that a ceiling fan is not installed. Considering the effort required to install the separate, independently switched conductor, this change does not add much of a burden to the electrical community. However, it does add an enforceable requirement for AHJs who did not have one before.
Where spare, separately switched, ungrounded conductors are provided to a ceiling-mounted outlet box in a location acceptable for a ceiling-suspended (paddle) fan in a dwelling unit, the outlet box must be listed for the support of a ceiling-suspended (paddle) fan [314.27(C)] (click here to see Fig. 1).