Instead of electrolytic capacitors, I use solid tantalum capacitors. Tantalum
capacitors are more expensive than electrolytic capacitors, but have better stability and reliability.
The ceramic capacitors are of the higher quality monolithic type.
When I layed out the board I was using JFET transistors in the TO-18 package. Now I am using JFETS in the TO-92 package that are easier to obtain.