G day Ed.,
my experience is that aperture is king, but test driving both eps and 'scopes should be the best way to decide what suits you. in case you can't do that simulated views at various apertures at Obsession
http://www.obsessiontelescopes.com/index.php and some beaut eye candy that will only exacerbate your upgradeitis
there are many excellent ideas in the forums here and elsewhere for inexpensive diy wheels to move a bigger 'scope very easily, especially for the short distance you have, and in case you have a step - ? diy ramp.
i have an 8" and a 16" and the 16 on removable pneumatic wheels get used ALL the time (its that convenient) and i have now loaned the 8 out.
regards, L