my dealings with trailers has me wanting at least a 18 footer. that extra 2 foot comes in handy about balancing the tongue weight on vehicles with odd weight points. also you having a trailer will make you a very popular person amoung your friends and nieghbors. no telling what they may need hauled.
this spring i bought a 20 foot trailer to haul my 6400 and coe on. it has worked out well, but wouldnt need the 20 foot if the big trucks were gone.