Should I have all lower teeth crowned?

The answer to this question depends on the current state of your lower teeth.  If you have a significant amount of wear or they are breaking, then I would consider having them crowned.  If not, I would leave them alone for now.  Good luck.  

It is possible and does make sense.  But first, are there signs of wear or breakage on the lower teeth.  If there are you may need to crown them.  If there are no signs of wear or breakage than probably you can leave them.  It is common to have porcelain on one arch and natural teeth on the other without any problems.