Hi and welcome to the K-5.
I have one and really like it. There is not a big difference between K5II and K5 so I would not worry too much.
You might want to check out Adams K-5 review where he recommends some settings:
Pentax K-5 Camera Review - Walkthrough - PentaxForums.com
It really depends on what you are doing with the K-5 and your shooting style, so there is no substitution for a bit of experimentation until you figure out what you like and don't like.
For me I live mostly in "P" mode (hyper Tv / Av is great), followed by "M" and now experimenting with Tav. Most of the default K-5 settings seem pretty good to me, although switching to manual AF points is a must of me. Oh and enabling "Allow aperture ring use" setting.