Can you provide a link as to what accessories you have to choose from?
I would not get zippered leaders. If you want to do ruler work find out if your machine needs a special foot for that. And yes, definitely get an extended ruler base. And if rulers are in the mix I agree on a set of circle templates and definitely a straight ruler but I find a much smaller size easier to handle. My most favorite straight ruler is 2" x 6". I have another that is bigger and I find it unwieldy and hardly ever use it. I would also get an arc ruler commonly used for curved cross hatching but you may wish to wait on these because there are many suppliers of rulers and the prices vary so you may want to work with the basics (straight and circles) before expanding your ruler collection.
Are there lighting accessories? What about an auto advance? Or even handle systems to make advancing easier.
Micro handles are an awesome add on to have if you plan on doing dense micro quilting and backfills.
If you need to use up the final couple of hundred, I would spend it on parts like an extra bobbin case, an open toe foot, a spare tension assembly and a couple of spare tension check springs. You will always need these things and it is nice to have them at the ready because needing to replace something always happens at the most inopportune time and you don't want to wait.