MC Phono preamp gains

Fully adjustable phonostage is d best.

^^ only if the phono stage is unstable. Loading of LOMC cartridges is all about the phono section and makes no difference to the cartridge other than reducing its output. The problem is that some phono sections act out a bit when presented with ultrasonic or RF energy caused by the resonance of the cartridge inductance with the capacitance of the tone arm cable (which is why loading seems to help). If the phono section is stable with this energy, you will not hear any effects from LOMC cartridge loading.

"Ihcho
So, virtually any combination is possible for all three inputs? Like, having all three as MMs, all three as MCs with different gains and loads, and mix of MMs and MCs?"

You are correct and it is very flexible

Or just buy anothen MM phono stage which is no expensive normally, why do you want them all in one cabinet ?

Well, which would be better. One phono preamp with three inputs or three separate phono preamps, if the price is the same.
If you go for three preamps, would you go for the same model for all three or different ones?
How about additional cables? How about space?
If Rhea costs $4000, would a phono preamp at 1/3 of Rhea be as good as Rhea?
Well, for me, it seems to be more complicated and less attractive if I go for three phono preamps. If I have three different phono preamps, I may end up using only one that I would like most, and then I need to change cables each time I try different turntables.
There are two used Rheas for sale now ($2400 and $2900), and they are out of my reach, but I will seriously consider it for my next phono preamp.

Many thanks for all replies.