I like to sometimes combine caffeine with amphetamine sulphate and/or 3,4CTMP.
Like this morning I drank a monster with 50mg of speed and 6 mg of 3,4CTMP inside then started a gaming session.
Without caffeine stimulants give a calm, serene high, not really any euphoria until I consume about 150-200mg, and I must drink that dose in less then 10 minutes for it to work properly, sipping slowly I will barely notice any effect.
I will also take caffeine together with MDMA or after the peak has passed, with 25i NBOME.
Caffeine does not give me paranoia in any combo I tried so far.
Cannabis on the other hand is instant anxiety and paranoia for me with no pleasure. And I mean, I will feel bad if I smoke like 20mg of good weed.