I've heard that the ET2 is not a good match with the SOTA, and may be the weak point in my analog chain.
Not true, I ran a Sota with ET2 for a number of years - it is a great combination.
The SOTA has a balanced hanging suspension and is much more stable than TT's like the Linn where the platter/arm sit on top of the springs.
You will have to spend a lot of money to get a better arm.
If you do want to go to a convection pivoted arm I would suggest the Kuzma 4Point 9 - one of the best arms around regardless of price. If you want a cheaper arm the Audiomods Classic or 6 punch well above their weight.
The Allnic is a good phono - why not just get it serviced and buy a new set of decent tubes.