For me...mostly what skystrider, dirtstrip and emflys said.
The tail pull handle that dirtsrip refers to can be bought here:
http://www.basinc-aeromod.com/I installed one on my plane and its invaluable for moving it around, also relatively easy to install, mine was actually made for an RV-8 and the builder never closed the deal for it.
Can't say enough about paying someone else to build parts for you not doing it all yourself, farm everything out that is possible, it will shorten the build time and keep you interested in the project. When you buy the kit, get it to the furthest completion level you can afford while still keeping you honest with the 51% rule. Tech advancements have helped a lot over the last few years, aluminum kits can be purchased with pre-punched holes, this saves an enormous amount of time, it's not just the drilling its the layout that takes forever, I have over 9000 drill holes in my plane...I know.
Get eevry specialty tool you can afford, they are great time savers, things like pneumatic rivet squeezers are not a luxury item in my opinion if you're building a metal plane, they save great quantities of time and pay for themselves. Avery tool and actually just about every other aviation tool company have one-off specialty tools, things like special tools that allow you to slide a washer in between surfaces where you can't fit fingers, anything that saves time is invaluable, it will help you finish sooner.
Hardware: invest early on and get plenty of extra, nothing sucks worse than being in the middle of something sataurday night and you don't have the right hardware and need to order something...it just slows you down, keep an eye on what you use most and always order many, many extras.
Don't underestimate the time commitment. Everything will take 2 to 3 times longer than you think. Try to do something every day if possible, even if its only to clean up. This will kep you energized...layoffs will kill the effort and the project.
I have a glass panel but did get a separte air speed indicator that starts at 20 mph, many of the glass panels don't kick in until you reach 40 and that's too high. I also added a separate RPM gauge that also doubles as a hobbs meter, if everything goes TU I should still be able to fly the plane with those two gauges, I kept them both to 2 1/4"..