I'll offer some constructive critisism from a newcomer's POV. I recently ordered a 66" P-51D Mustang, and it is yet to arrive so I cannot offer any quality suggestions.
1.) Looking at your Scale RCs, I do notice that many of them do not come with flaps. It may be worth talking to your suppliers about redesigning these airplanes with flaps to more closely resemble their bigger counterparts. Plus, flaps help.
2.) Yes, shipping is expensive, but do you have much control over that?
3.) Offer construction manuals online so builders have time to gather the needed tools to get right to work on the plane. Also gives them time to study.
4.) Put some videos up on your website. Show us how great your birds fly.
5.) I assume your niche would be price. Keep it up. Black Horse Models are around $50 more, but include flaps.

Keep in mind I only focused on what you could improve. In no way am I saying you are bad, or else I wouldn't have bought from you. Keep your business model. The customer likes to know you are there not only to make a profit, but keep having us come back when we make a dumb decision and wreck our planes. Hope this helped. Keet it up Nitroplanes!