The negative consequence there is that often times we don't learn about ourselves until we attempt to make such a change. If you hate debugging Java, and you can take a pill that makes you not mind it, you might never discover that you could actually be a much better Ruby programmer than you ever were a Java programmer -- or that you really were never cut out to be a programmer at all and should pursue something totally different. You'd just chug along debugging Java your whole life and never realizing your full potential.
> If you gave me a perfect happiness drug, I wouldn't want to sit in bed all day and take it. I would want to take it and go about my normal day only without the burden of misery
I've been reading some meditation related books lately, and this was one of the ideas they were trying to get across. That meditating for a sense of fulfillment doesn't replace your desire to go about and do good work, it merely changes your perspective on how you feel while doing those things. Additionally, it (allegedly, convincingly argued) enhances your ability to do the things you like well, and to make better choices in general.
> I suspect this is just because many of our current drugs do this as a side effect of inducing euphoria, and we're imagining that instead of a real happiness drug.
A useful way to contrast that is with uppers. I took my friends aderall a few times in College - in addition to staying awake, I felt profoundly happy - yet I didn't give up my goals (study all night) - I merely had a good time doing them.
I know there's some science around parts of that - far too lazy atm to search and link it (sorry!). But perhaps it is a bit counter-intuitive that feeling deeply happy and satisfied could also drive a person to do more meaningful work at the same time.
If there were a beverage that worked like coffee except was more MDMA like, that our physiology could sustain in daily use, I dare say a lot of us would drink it.
Reason is a poor way of estimating behavior, in special, your own.
This doesn't compare with anything a normal person experiences during life. There's no rational expectation to be had of how anyone's behavior would be if such a drug existed.