So where should the tubes be?

For me it is easier to count where tubes are not.  Uhm, CD Transport, power conditioner. 

like so many things in life, more is not always better, in fact it is usually not

the right amount is the right amount

making who has the most tubes in their system, as if it were some kind of competition for the best system, is utterly ignorant and foolish

My use is at the pre amp. Can’t say if this is right wrong of best just what I am doing. I did read a few articles that stated they felt this was the best place to start. Also said with tubes in pre and ss at amps their is less chance for down time. If a tube goes out on your amp you are dead in the water. If a tube goes out in my pre amp I can by-pass tube stage and still keep rocking. Can’t say I will remain where I am for ever but happy with my sound for now. Enjoy the music any way you can get it.

The only tubes are in my tube phono stage. It just made sense to me to go analogue into tubes the sound is incredible. 

I agree tubes everywhere. But if your starting and want to wet your feet before you commit, phono pre, dac, preamp first, amp last. IMO