Possible Upgrade Advice

I have a Scoutmaster/Dyna 20X 1.0mv VPI version on the JMW9 arm, using a Rogue Magnum 99 pre, looking for a little more detail if possible. Any advice in the $1500 or less range?
Try a Lyra Delos cartridge and/or maybe get the Valhalla wiring for your JMW9 tonearm.
The Valhalla wiring would be a step backwards....sure it sounds more extended in the highs (bright??) but is not nearly as musical as the Discovery.
I have heard both Discovery and Valhalla, there is no doubt the Valhalla provides more detail. Now, whether you want more detail or more musicality is up to listener, just as with all cable choices. The OP seems to be looking for more detail.
An Ortofon Cadenza Red is a nice and detailed cart for under that money, and
it's kind of between low and mid output MC range, to where your 99 w/ its
tube phono stage can probably stretch it -- I believe that tube stage has a
tube-sub option (e.g. 12AU7 => 12AT7) to raise its gain, which when
combined with the line-stage's very high 23dB gain should be sufficient for
the Cadenza. You definitely don't want to go to super-low MC (0.3mV or
lower) without a dedicated MC phono stage, though.

Another good option down the road is to upgrade to a Rogue Ares phono
(more detailed than the 99's stage for sure, and even better if/when the stock
SUT is upgraded), and then to upgrade the line-stage with an Athena (big
jump up from a 99, sonically). You could also get your 99 super-magnum'd
by Rogue (beyond the magnum status) if you don't want to go too far &
expensive on the preamp upgrades just yet.

I'd also stick with the Scoutmaster; great table if you're OK with the arm.
Latest model DV P-75 MK3 sells for $895.00 and matches really well with DV carts and this one supports 1mV MM/MC carts. Improvements over MK1 and MK2 models include:

•Multi-layer printed circuit board for even lower noise
•New output amplifier for lower noise and more drive current
•More headroom from internal power supply
•More loading adjustments, including user fitted R & C
•More gain adjustments
•Power supply polarity switched to center positive

I use the MK1 version with a Lyra Delos with GREAT results.

happy listening!

As a follow up guys I did some adjusting of the VTA/SRA and I don't think I need anything now!!! What I am hearing now is staggeringly better than what I had!!! I can't believe I thought it was right all this time...
Cool! Saved yourself $1500, and learned the importance of proper VTA/SRA set up all at once. Did you re-check the VTF? Changing VTA will affect VTF as well.
Yes it needs to be adjusted some too!!!
Nice Jsman! Also changing VTF will change overhang, this should always be checked after VTF adjustments.