Forward Sounding Speaker Crossover Components - Suggestions?

An excellent source for advice and caps is Michael Percy Audio.

@steakster you're the 2nd person to suggest him to me. Coincidentally I reached out to him with the question while simultaneously working on an order for Jupiter caps. His response: "Very difficult to speak definitively about any particular capacitor's sonic presentation. So much depends on the particular loudspeakers, and the electronics driving them." 

I like performers in room presentation, modded a number of speakers and crossovers over more than a decade. First off, electronics, pre's, amps, sources are greatly responsible for sound staging, so that good place to start. As for crossover mods, my intention with these mostly for gains in resolution, transparency, more natural timbre, wasn't looking for sound staging presentation to change per se. Having said that these mods did affect sound staging to some degree. Generally, I've heard more dimensional images, larger sound stage such the illusion of performers in room much greater. So, speaking in generalities, SET amps, DHT pre's and physically large horns do it for me.

As for specifics with crossover mods, I've used Duelund, Jupiter, Audyn caps, all very nice, specific models in these brands will give you exact voicing. For what its worth, at present using combo of Jupiter VT with Audyn True Copper Max, Jupiter VT bypassed with Duelund Silver bypass cap. Jupiter VT is a more  laid back cap, Audyn more up front. Also love the Jantzen air core inductors, solid core on mids/bass, wax impregnated litz on tweeters, both top notch, may amaze you depending on current inductors. Internal wire important as well, I like Duelund tin plated copper. By the way, these on Klipschorns, custom drivers, Volti tractrix horns, custom tweeter baffles. I also modded Merlin VSM, Omega, and others in the past, always to good effect.

Since Clarity Caps have been mentioned I add my experience with then .  I Recapped and resistored my crossovers in phases , first I tackled the woofer using CC CMR cap on the positive and an CC MR cap on the negative ( because of size ) , these were the top of the line at the time .  When the Pure series of caps came out (I waited over a year for them ) I used them for the tweeter and mid range and I will definitely recommend them , they have the same features as the CMR and have been improved also they are slightly smaller . 

As for resistors ( they too make a difference in sound ) I used Mills throughout . 

Capacitors, inductors, resistors have ZERO to do with imaging and soundstage. Instead I suggest you buy a pair of speakers that will give you 3-D dimensionality from anywhere in the room - Ohm Walsh's. I have a pair and they are indeed the best at bringing the performers into the room!