Investing in the bitcoin is very good, only a little amount is already enough if you ask me due to the point the bitcoin will got to a high amount.
I think investing with the money you have in the bitcoin can be good because bitcoin can collapse but the next few years this will not happen.
Generally speaking, I agree with you, if someone spend in bitcoin is good but not spend all of what he has!
I think that's correct, always have few coins on safer side, as we don't know where bitcoin will reach in future, so its better to have few coins in cold storage and don't touch it unless the price reaches to your satisfaction level.