For B12, I like this spray:
http://store.veganessentials.com/pure-advantage-vitamin-b-12-spray-p1158.aspx (though you should have enough stores of B12 to not feel any effects of low levels for a while).
For potassium, you say you hate bananas, but what about frozen bananas used to sweeten/thicken smoothies?
Other sources of potassium: coconut water, oranges, avocadoes, carob
I found this info:
" If you eat plenty of fruits and vegetables, then you are probably consuming enough potassium. Particularly good sources of potassium include bananas, tomatoes, cucumbers, eggplant, pumpkin, spinach, raisins and root vegetables. Generally, more-processed foods have less potassium."
Best to get it from foods:
"
What happens if you get too much?
High potassium intakes from food have not been shown to cause adverse effects in healthy individuals. However, high doses of potassium from supplements can be toxic. Toxic doses of potassium supplements can cause a range of symptoms from gastrointestinal distress and abnormally high blood levels of potassium to heart irregularities. Bottom line: Stay within range of the recommended intakes"
(quoted from
http://www.bing.com/health/article/...RE&qpvt=food+sources+of+potassium#bestsources )
For vitamin E, almonds are a good source, as are many grains.