Hi Nikita,
You seem to have gotten some excellent advice from Zebras already, so I don’t have that much to add. In terms of adjustments there is not much you can do on Roger Focus. You are basically limited to the EasyGain adjustment, and that you can already adjust directly with the volume control on the device, so no need to get a Select or Touchscreen mic for that.
In the Roger Focus FAQ the last point mentions that using an earhook would give about 8dB of additional gain. That corresponds well to the difference you are describing as you say you needed to turn down the volume to the minimum setting, which would be -8dB. Not sure how plausible it would be that you trialed devices with earhooks attached though…
Considering that you say you get a benefit of wearing Roger Pen in omni mode, I’m thinking it might make sense for you to try using hearing aids. A standard Marvel is probably enough, like an M50. No need to get anything fancy as you seem pretty content with the Roger Focus. Hearing aids would allow for far more adjustment possibilities, but it also comes at a price of course.
If you are thinking about getting an additional microphone I’d advise you to go for Roger Select rather than the Touchscreen mic, as it is more suited for social situations. The select feature allows you to choose what directions you want it to pick up sound from. It works much better on a table than Roger Pen if there is a bit of background noise or if there are multiple conversations going on.