There's more to level flight than a nice square build. CG and control surface trim would be two major ones. Also motor size (Put an oversized engine on a smaller plane and wide open the throttle and whatch her climb). You want to make sure the build is all square and both wings are level with each other and you will be good to go. First flight will almost always need a little trim clicks. My last plane was a Goldberg Tiger 60 ARF. When I finally maidened her, she didn't require a click of trim anywhere. I was so proud of Carl Goldberg and myself! :LOL: That doesn't happen often!