Keyboard Viewer for Academics

I'm a graduate student in Chemistry. As such, I type a LOT of reports. Unfortunately for me, writing in Science isn't QUITE the same as writing in English. There is quite of bit of Greek involved as well. Now I love the keyboard viewer, and being able to see some of these frequently used Greek characters, such as ∑π∆∂ßΩ and µ. But some of them I'm hard pressed to find such as γσδηρ, and so on. The character palette is less friendly than the keyboard viewer in terms of sheer ease of typing. Is there a way I can either:

1. Create my own custom option-key enabled keyboard layout with all the greek letters I want.
2. Customize the WYSIWYG option menu for U.S. language?