Some cartridge recommendations

To unleash the expected flood of bewildering recommendations, what is your budget?  Also, try to find out what is the effective mass of your tonearm plus headshell.  (If you're using the OEM SME headshell, then usually the mass of the headshell is included in the manufacturer's spec for "effective mass".)  Then add the weight of whatever cartridge (typically 5-6 gm to less than 15 gm).  And you can then select a cartridge with suitable compliance to keep the resonant frequency within the accepted range of 8-12Hz.  (There are automated calculators on line.) OR, ignore all that crap and get a cartridge you like and can afford. In actual practice, most cartridges work with most tonearms, unless one or the other is wildly different from the norm.

The mass of the tone arm is 9 grams w/the detachable headshell, which it does have. Budget is $1,000.00 plus or minus a smidge. Hopefully minus. 

Audio Technica OC9 or Hana

Unfortunately there will be a few who will frown upon your TA, but it is the Improved Series II, so a wider range of MC's can be considered.

For an idea of what can occur, a friend and I were comparing same design > manufacturer Cart's, with slight differences to their designs due to one Cart' having been sent to a Third Party Service.

Both Cart's were mounted on the same Headshells Designs with a SME Bayonet connection.

Both Cart's were replayed initially on a SME 3009 Series II, which was substantially fettled.

Both Cart's sounded very very wanting.

On another occasion, a TA was used that was much more of a match to the Cart's being used, and it was without doubt, both Cart's had excelled in improvement of the presentation.

Caveat Emptor is the guidance when selecting an MC for your TA.

The Ortofon MC10 already selected is possibly one of the better matches, or even the MC 20 - 40.

Thank you for the response, that is the type of info I was hoping for. No reason to get a different cart if will not be a good match and hopefully give better performance, Allen. 

FYI, I inherited this set up from my 92-year-old uncle, it is very vintage and mostly unused. I was looking to see if a more modern cart would be a good idea. Sounds like possibly no. I also have all his vinyl (in very good condition) and was wanting to get playback a little closer to what I am used to. A bigger sound stage and frequency response at both ends. This set up has good tone just seems a little flat.