The strings we have been using for our own guitars are Savarez Alliance basses and New Cristal trebles, both high tension.

 

Medium tension usually produces a sweeter tone and more responsiveness, but there is a greater chance of buzzing on loud notes.

 

I believe our main supplier puts medium tension on all its guitars, including Ramirez.

 

Savarez Corum basses supposedly offer more resonance for a given tension, i.e. a high-tension sound with medium tension strings.

 

For someone who plays without nails, carbon fiber trebles will sound brighter.  You have to be very careful with these strings, because they are thin and can slip off the tie block.  This will result in a dent in the top of the guitar.

 

To avoid this, tie a knot in one end of the string, and wrap that end of the string around the tie block. 

 

Hannabach trebles are piano-like, and are worth a try.  So are their Silver 200/900 basses. 

 

I was also impressed with Hense strings, but need to experiment with them on a wide variety of instruments.

 

D'Addario Pro-Arte high tension strings have become somewhat of a standard among many guitar builders.  I like their basses, but the high-tension trebles have a dense sound with diminished color possibilities.  Medium tension D'Addario trebles have a better color range.  Their composite basses, which supposedly last longer than conventional ones, are popular with many classical guitarists.