Also what grain arrow/broadhead would be best for whiletails/black bear.
There is no set rule concerning this. You are looking for a good ballanced arrow with about 10 - 15% front of center weight. If you choose a light weight arrow a 100 grain head will most likely work out well for you. If you choose a heavy arrow then a 125 grain or heavier may be best for you.
I personally prefer 450 - 500 grains finished arrow weight for everything. It gives me good speed and a good quiet bow. I find this weight range to be a very good compromise for me shooting 70 pounds and 30" draw length.
And slicktricks, worth the hype?
You bet your a$$ they are.