Best speaker crossover caps for deep, tight, detailed and tactfull bass?

I find Audio Note Kaisei non-polar electrolytic caps work great in that position. They will fit easily and sound better than the bottom and lower tier film cap offerings in that position. They just do! Wonderful for bass.

Combine a 50 & 22 uf set. Pay to have them matched within 1% of the needed 72uf. 

Film caps in that value will be both huge and very expensive! For electrolytics grannyring's advice for AN Kaisei good. I also recently used the newly released AN Seiryu in recent pre upgrade, very nice electrolytic.

Generally there are no capacitors in series with the woofer. However there usually  is at least one inductor in series with the woof. The lowest series resistance will usually give you the tightest bass. So chose the series inductor accordingly. Most speaker companies use some form of ferrite or iron core inductor to achieve the lowest series resistance.