The larger certified airplanes set their trim so as to be in trim for the climb speed. It usually varies with weight and CG. I guess the RV 6's CG doesn't change that much with weight, not like a 4 or 8. But if you put a bunch of baggage in the back and move it aft, the required tab position to trim at a given speed will be different. So what the bigger airplanes do is define a "green band", which is a range of trim setting for forward to aft CG, such that if you are set anywhere in the green band for takeoff the forces required to trim will be small. So that is usually the range between heavy weight forward CG and light weight aft CG. And it will change with flap as well. We are required to demonstrate that if you have the trim set for heavy forward (nose-up trim) and you are actually at light-aft, the resulting forces are not too bad. They call this test "mis-trimmed takeoff. This often defines the width of green band.
I know this stuff is all FAR25 (transport category airplanes) and there is no legal requirement that homebuilts conform, but these principles have been developed over 100 yrs and they work well. Somebody figured out a long time ago that 1.3Vs was a good speed for approach, and that works for homebuilts too - deviating significantly from this is probably not a great idea. And that there were certain things you should do and should not do in terms of cockpit design and human factors. All those lessons are written in blood - they mostly came out of the knowledge gained from accidents. Making your cockpit work differently than most other airplanes is probably asking for trouble. So these requirements provide very sound guidelines for setting up one's airplane in many areas IMHO.