The answer is not that clear as it seems.
If you plan to be long time miner with beeing the most effective in 3 or 4 weeks, than you should go direct to control Termis (advance robotics 1, indu bot control 5), spend as less extensions as possible now in mining cycle reduction (Extensive Mining 3) spend as less EP as possible in CPU and reactor extension to equip your termis (e.g. mixture of Data Processing and Optimized Industrial Engineering for CPU) and put all other EP in "Accu Expansion" and "Energy Management" until your Termis is capstable running, than increase mining effciency with EP split between general and ore dependent to get the best mix (highest result if you focus on one ore first).
If you talk about most effective today, you should be better off with Argano mk2 with T4 small modules, and spend EP in Cycle Time reduction, but this will most likely hurt in 2-3 weeks.
BTW I consider it a valid idea to not getting capstable with 4 med miners in Termis, if you are close for entering Riveler, as I think in Riveler it is more easy to be capstable.
And for general cap stability there is a difference between mining ore and liquizits. You can be capstable on Titan, but experience getting instable on liquizit, just due to the fact, that on long term you recover during tile change the necessary small amount to stay stable.