High dose is relative to your tolerance level but yes 6mg is a high dose. I'd say even 4mg is a high dose even though it's the dose I'm scripted, personally, but again it depends on your tolerance.high doses being in the range of 6-8 mg?
do you think combining with Pregabalin could be dangerous?
Pregabalin will potentiate benzos. It's not physically dangerous as such, but it makes blackouts etc more likely since you get stronger effects, so just watch your doses.