Not really, or at least, that's not the intention. The suggestion that Mellel urgently needs to add features is not so much because existing users want them (although we do, of course) but because that way Mellel would reach a market of technical writers, academics and others who want to do (potentially) long document production with good typesetting and light page layout without resorting to LaTeX. That market certainly exists but is not served by any OS X application.You're asking to add new features that speak to your specific needs rather than asking the developer to improve his product for a potentially larger market.
Another niche that Mellel has only partly reached is the niche for a really capable multilingual word processor. Again, there is no such thing on OS X.