This is an old thread, but I thought I'd comment anyway since I just converted my Flight Design CTSW to E-LSA status.
Unlike CSA, FD is willing to issue LOAs (they call them MRAs - Major Repair/Alteration Letters). But they charge for them. For tiny, insignificant changes like adding a piece of equipment that is already installed in other CTs, the cost is a $75 fee. For more involved changes they charge for an "engineering study" to see what the change might do, which can be $500-1500. I was quoted $900 for an MRA to change my straight pitot to an AoA pitot to use the AoA display in my D-100. I said "never mind". Note that most of this comes from FG Gmbh in Germany, the FD USA guys are very accommodating and have a "sure, sounds reasonable" attitude, but they are constrained by the German folks.
I took the Light Sport Repairman Inspection rating course, and so now I'm legal to do condition inspections as well as any other maintenance on my airplane. In the past month I have completed my condition inspection, as well as the five year Rotax rubber change, and replaced the motor mounts on my airplane. It was time consuming work that requires attention to detail, but wasn't particularly difficult. I'm always careful to consult "experts" before tackling any new task, to make sure I use the correct parts, techniques, and miss any "gotchas" in the process.
As for lost sales value going to E-LSA, I had two DARs tell me they didn't think it would affect sales price at all, as long as I didn't make major or obviously sketchy modifications. Also, so far just in the just the short time the airplane has been E-LSA, I have saved about $2500 by doing maintenance myself instead of paying to have it done. Given that and what I have averages annually on maintenance, I am very confident that any potential loss of sales value down the road will be more than offset by maintenance savings over the years I plan to own the airplane.
I'm very keen on the E-LSA option, but obviously everybody has different skills and priorities, and some don't want to take on maintenance. But for those willing, I believe the financial considerations are a non-issue. I'm not even convinced they are a major problem for those choosing to continue paying for maintenance on an E-LSA. I think the key in either case is work that is performed correctly and well documented, so that the next owner is confident of the provenance of the airplane and its maintenance and upkeep.