Hi Fithy,
It seems that a persons response to having a partial meniscus removal is random. Some can have no issues, presumably as they retain sufficient joint spacingbetween their articular surfaces due to lucky bone architecture (i.e. bow legged or vice versa depending on the part of meniscus removed) or movement patterns that tend to not reduce the joint spacing further in the compromised compartment. I wasn't lucky and like you had to give up on sport after a partial lateral meniscus removal, and then 2 years later, after trying to return to sport but lots of reactive swelling, I had managed to completely wear through my articular cartilage.
I think you have a few things you can try. If i could go back in time with my current knowledge I would seek out my current Osteopath (she has additional specialisations in Neural Kinetic Training (NKT) and Functional Range Control (FRC)) and have her figure out if anything could be done with respect to my movement patterns and body condition to relieve stress in knee. I'm amazing how much positive progress I have had since investing time with her, the last year has been trans-formative.
If that is exhausted I think you would be talking about attempting a unloader sport brace (I wear an ossur Custom OA CTI brace), hopeful that it can create the necessary joint spacing for you when occasionally playing. I have one and wear as an instrance policy to prevent an abrupt collapse of my lateral compartment if someone bashes into me (I am an ice hockey goaltender).
Last resort (as it should be) is surgery. Perhaps others would consider types of injections but my experience with injections is just steroid joint injections, which I regret. You might be talking about a meniscus transplant but, having gone down that route myself, I am finally match fit and it has been 2.5year post surgery, so a massive chunk of time and takes over your life, so a decision to be taken only if sport "is your life" essentially. Even if you are prepared for that time investment, the outcomes of surgery won't always be better than your current circumstance, so you are rolling the dice.
Hope that's helpful, I am a strong believer that the right Osteopath can do lots to help someone.
Regards
James