Some cartridge recommendations

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. 

With being New to the use of Vinyl, there are a few things that can be considered, which are not too expensive and will improve the sound that is being produced from the Vinyl Set Up if all other ancillaries needed to replay vinyl are in a good condition.

There are also forums with dedicated Threads to the SP10, but usually found under the Technics Brand name, I'm sure there are Threads to be found for the 3009 as well. 

Have a look into the mounting of the TT, is it on a very rigid support structure, not influenced to move by movement of the rooms floor?

If the Support is seemingly very rigid, the TT, can be mounted on New Feet (Improve Isolation) or a Sub Plinth with different Foot Types to support Sub Plinth and TT (Additional Improvement for TT's Isolation).

If there is a Vinyl Collection Inherited, there is considerable improvement to found for the Sound Quality when cleaned Vinyl is used.

None of these incur too much cost, but will be very advantageous to ones experiencing Vinyl being used, especially when the time comes that purchases are being made of replacement ancillaries