And ê, when pronounced (most of the cases) it's just a è.

ë, contrary as said in the article (full slop?) is the most complicated and with some exceptions. But there is so few words that use that letter that you just don't have to care.

Just pronounce ë as è when its in (inside) a word and not pronounced at all when it's at the end. The only exception I can think of is canoë (pronounced conoé), but everybody will understand if you say cano.