Well I am definitely going to finish out the Dragonfly and I am pretty set on the Long EZ, although the way prices of materials and shipping are going it is just about cheaper to buy a flying plane than purchase the materials! My "original" plan was to finish out the Dragonfly with the Corvair motor and fly it as much as possible. As I get closer to the checkride I am revising that plan. In fact I purposefully cut back on working on the Dragonfly as I am aware of my proclivities and know full well if I had both a flying plane and the certificate in my hand temptation would get the better of me and I would start flying it before I probably should.This thread feels a little like deja vu.
As has been said, mission is an important starting point. I started out looking for VW powered stuff because of, well, limited funds. The Sonerai and the KR2 were a couple of models that were initially high on my list, until I sat in a couple (and I'm much smaller than you). While I was still a student, I bought a Dragonfly that only had 3 hrs on it, and moved it on a trailer (and the roof of my car) to my local municipal airport. Got it reassembled on the ramp (different days), and an instructor acquaintance made the new 1st flight. Around the pattern once and back on the ground with a melted piston. After Viking (the original) rebuilt it, a different CFI acquaintance did the next 1st flight. Another melted piston, but this time 3 porpoises and a broken canard on landing. I lucked out and because the original builder sold to me so cheap, I was able to recover almost all my investment when I sold the wreck.
Obviously not a pleasant experience at the time, but things actually worked out better for me. I ended up buying a 1/3 share of a Luscombe 8A for less than I'd paid for the Dragonfly, with the seller (a CFI) ultimately becoming a good friend and taking me all the way to my private ticket without charging me. Even bigger, it opened up another entire universe of flying for me. If I'd been able to continue with the Dragonfly, I would have missed out on grass strips, which have become more frequent destinations than paved airports. It more than doubled my options when flying purely for fun. It also greatly opened up the number of options for my 1st homebuilt purchase, since *many* of the great deals we're likely to find on the homebuilt market have the little wheel in back. My 1st homebuilt was a Thorp T-18, and the Luscombe was great prep. After about 60 hrs in the Luscombe, the T-18 was a no-brainer to fly. Still good for grass strips, and the strip where I first flew it is now where I live & keep my planes.
Your goals are your goals; just be aware of all possibilities before you make a choice.
BTW, if you have to tie down outside, a fabric covered a/c may do ok for a short period but I'd plan on long term issues, especially if you're in the south. And as much as I like alternative engines, I'm honest with myself that they are statistically likely to require much more 'fiddling' and maintenance than a typical traditional a/c engine. Most of the smaller traditional a/c engines can be operated at roughly the same fuel burn as a VW or Corvair, if you're willing to pull the go lever back after takeoff. ex: I fly my 180 HP RV6 locally at ~5.3 gph. A small Continental in a relatively clean light airframe will be well under that, and not be always on the edge like a VW. The downside for any of the old certified a/c, of course, is the need for an IA at annual time and the ever present risk of ADs on those old designs. A homebuilt with the small a/c engine lets you use an A&P for the annual, with little AD risk.
Metal Luscombe, metal C120/140, and of course the batch of metal nosedraggers, if you decide you want to stick with Dragonfly/VE/etc type aircraft in the future.
As far as the VW engine, I have a fair amount of familiarity with it and will not need to run to an A&P to fix or sign off on issues an old airplane will surely have.