Danny, those "old" lamps are there to keep the cats off of the speakers. Besides, both of those lamps aren't old, they have very nice LED's in them!
By old lamp stands I was referring to the speakers.

Regarding high loss cabinets (unbraced and highly resonant): This older speakers were built to a price point and lightly built for that reason primarily. Also, back in the day most speaker companies simply didn't know any better or didn't care. Seldom was it on purpose. The highly resonant cabinets add a coloration to the bass and mid-range that some people really like, but it is an artificial addition and not part of the original signal. Think of it as running the signal through a reverberation device before amplification. It might sound cool, but is added coloration unquestionably.
Regrading cap and coil upgrades:
Any time you are using several caps to make on value then you want to avoid using various differing values. By that I mean that you don't want to use a 6.0uF and a 9.0uF to make a 15uF. The discharge rate between the two caps are different and one will lag the other causing a smearing effect. Using a pair of 7.5uF values avoid this problem. When you drop a really small one in there though that is a .22 or a .1uF or smaller then the phase shift caused by the smaller cap verses the larger one is higher in frequency than you can hear (above 20,000Hz). So effectively you are discharging the larger cap and reducing it's stored energy with the larger one. No problems with that.
The Jantzen caps are not bad caps but results can vary with application and cap type. Several of them are known for having a flavor of there own.
Their inductors are fairly reasonable (price wise) and especially considering that they have to be imported from Denmark, and a 5% duty is added to their price, plus heavy shipping cost because of the weight. And they are cheap for good reason. Independent tests have shown that the Copper is recycled and about 94 to 96% Copper. The rest is whatever trash got mixed in during recycling. A/B comparisons to other inductors further confirms this to be the case. So I don't recommend those inductors.