Do number 1. Seriously. First of all, consider what you really need. If you're adding stuff that's going to enhance gameplay or storytelling, that's great. If you're adding stuff just because you want to be able to wave a sign around about how you're as good as everyone else, that's a fools errand. There'll always be some new trick, some cool little feature that you'll want, and if you try to do everything, you'll never do anything.
Now, as for bringing someone in to add new features onto other people's missions, I've gotta say, that seems to me like it'll be a headache, long term. FREDding is very idiosyncratic - there're multiple ways to do almost everything, and every FREDder does things slightly differently. Digging into someone else's mission will be much harder than digging into one of your own if you're making big structural changes.
Which actually brings up a third point - what exactly do you want to do? "Cinematics" is pretty broad, and the basic stuff can be picked up by any half competent FREDder. With that, it's simply a matter of a few hours practice - there's not a hell of a lot to learn. Once you understand what the various sexps do, the only limit is the imagination of the FREDder. And 'scripting', well, scripting is an entirely different skillset to FREDding - I consider myself a pretty competent FREDder, and I couldn't write a line of LUA if you paid me. Moreover, scripting is a means to an end. If you have some specific thing you want the engine to do it can help there. But it's not a magic "make mission better" wand. If you have something like that, you can probably ask an established scripter to write you up something, rather than letting it hold up development while you wait for someone who wants a badge.
