Regarding dew, a shroud will make a big difference as will putting a baffle over the end of the scope behind the primary as per Scott Tannehills article
http://www.iceinspace.com.au/63-400-0-0-1-0.html You won't need to remount the fan as he suggests, but the little baffle around the inside circumference of the OTA just above the primary works well. When I did this with my 12" GSO, dew became a thing of the past and the primary mirror cooled much more rapidly. You'll need a shroud for it to work for the secondary though.