well for the last decade I've been lopping off any connectors and replacing it with either a dean ultra plug or a deans mini plug. Except radio gear, their stuff just fits will minor mods.

as for the prop ream. there are standard and metric so make sure you know which to get. As for the prop manufacuerers and standardized hole? A drill bit works just as well, the reamer is meant for it and nessasary for the feild. There are allot of other tools you'll evetually own if you stay with the hobby. I added it up the other day I think I have like 400 buck is tools Not all my tool just the tool for spcific task for model planes. mostly for building them.

the hobby is a whole lot better off than it was a few years ago as far as newbie gear goes. I think tower has always gone a great job of getting most of the stuff ya need to get a model going, it's the only site I've seen than list the stuff you'll acually need and relavant to that model.
If ya think it's tuff with newbie gear wait till ya build a scale kit, product compadibility is just the tip of the iceberg. For me it's all part of the fun of learning. By my fifth build I think was the point I could make one order and have everything I needed to get the kit done and flying. Before that it was pretty frusterating learning what I did and didn't need, what worked what didn't and what was crap.