are older Naim integrated amps considered high current?

What are you trying to drive, how big of a room and how loud do you want it?  Most speakers don't need alot of power to make loud noises, typically they only draw a few watts in most usage, but that really depends upon those 3 questions. The NAIM XS is very impressive for its size and weight but there may be better options in that price range depending upon your needs. Personally I'd look for a Willsenton R8. 

Not necessarily.  It all depends upon why OP is asking about current. I'm assuming its because the XS is rated at 70 watts and they are worried it will sound thin and anemic and won't properly drive their speakers.  They probably read something about current being more important which adds to the confusion since power is still generally specified in watts. The R8 has an extremely thick and robust sound despite only putting out 25 or 45 watts. Meat on the bones as they say. I can't think of many other integrateds in its price range that sound as full bodied and smooth. 

Now on the other hand, if they have concerns about current because their speakers are difficult to drive and dip well below 4 ohms like electrostats, or speakers with an array of drivers, then yes, avoid tubes. But that seems unlikely given the price point of the integrated.