Thanks for all the answers.
After reading a bit through some of your suggestions, specially the
synth secrets articles on FM (which I had read sometime in the past) I
know at least know what to expect when tweaking the tuning settings for
the operators.
Still, from your comments it seems it takes mostly experience to achieve
a certain kind of sound, so I'll take that route for the time being.
I did try dexed, but the vst ports from distrho seem more resource heavy
than other older plugins such as hexter, so I'm sticking with the latter
for the time being.
I'm still open to any suggestions though.
As always, have a good one!