Should I recap my speakers? If so who can do it?

Here's your problem. I tried to upgrade some Vandersteen 2CE Signatures once. They actually have 3 capacitors in series, so I bypassed them with V-Caps. The treble sounded horrid, they used the 3 caps to tame the tweeters. So, if you send the crossovers out and the speakers sound bad, you are not going to know why, or where to begin to address your problem. It's far better to deal with someone local who is doing this as a hobby. If you could ship the speakers it would be different. I did do a set of crossovers for a friend long distance, and we got lucky, they weren't trying to hide anything. I'd highly recommend that you learn to solder, and learn electrolytic capacitors, that is polarity, vs non-polar, etc., well enough to do the work yourself, or deal with someone local. Things you can ship, like amps, preamps, and such are fine to ship as the modifier can tell if a component is a problem or not. I am not trying to hurt anyone's feelings or business here, but experience has taught me that if you either don't have the entire product available or haven't previously modified one, it's best not to do so long distance. It could work out perfectly, but if there is an issue, how many times are you prepared to ship it back and forth to address it?

I've been kinda arguing with Invictus005 on a couple of threads.  His points are actually correct that a polyprop is better than a mylar and a film & foil is better than a polyprop and a styrene is better than a film & foil and a Teflon is better than a styrene, but that doesn't make a Teflon the best for everything or any part the best or worse for every application. 
 lous just made my point perfectly. The original VCaps are Teflons… on a very detailed or maybe a slightly edgy tweeter, they will accentuate all the issues of the tweeter.  That tweeter needs a cap that is more forgiving.  You can't just put all of this in a can and say that this is how things are.  It requires a basic knowledge of every speaker that you are working on before choosing upgrade parts. 

I don’t quite understand why someone would use a speaker, or whatever, that is less than the best, sometimes it’s to meet a price point, other times I’m sure it is for other reasons.

For me there are pretty much 2 paths. The Vandersteen path is an attempt to make everything sound good, regardless of how poorly recorded it is, etc. This is done by going dark, muting the highs to be sure, and with some really poorly, IMO, gear, everything. Vandersteens mids, if memory serves, are pretty awesome, and the bass too is good, but the highs sound like a great set of speakers with a towel over the tweeter. IME, that type of gear should be left alone. If the bass is weak, it’ll take more than caps to fix it. I am generalizing here, but it tends to be more often than not the case.

The other side of the coin is the hi def/ hi rez side. Attempting to get every drop of detail possible out of the music. This is where I live, and it is certainly more challenging. You can get very transparent gear, even some bright gear, mate it with Vandersteens and it’ll still sound pretty good to folks seeking the Vandersteen path. With my system, one bright piece of equipment will drive you crazy, you just can’t listen to it. OTOH, pleasing colorations like tubes are also more apparent, and generally more enjoyable. Cables are more critical, teflon caps are a plus because you can only afford to use well designed well balanced equipment.

As for the crossovers in question, my experience with Mirage speakers, limited though it be, is that they are reasonably, to very transparent speakers. Therefore, it isn’t unlikely that a remote crossover rebuild will turn out well, but that is an opinion formed out of generalities, so it could very well be as wrong as wrong can be. The safest bet is to work on it with the speakers available so that you can immediately make corrections if need be.

Info on charistaristics / sonics of caps
http://www.humblehomemadehifi.com/Cap.html

Since some capacitors require "hundreds of hours" of burn in, which in itself may be questioned, there will innumerable other changes in line voltage, RF, ambient temperature and pressure, user acuity, etc. so as to make the ratings quite possibly specious.