Uh-oh, lookout! Here comes Pete.
LOL. Welcome to the group Pete! You are on a slippery slope now.
Though if you already have a large Pentax collection, you may be less inclined to fill out an Olympus kit.
If you are not too happy with the 50mm f1.4, try the 50mm f1.8. It seems better edge to edge than the f1.4.
Another lens that I would reccomend is the 100mm f2.8.
Not sure about the slower wides.. mainly because I have the 28mm f2 so I have not picked up any of the slower cousins yet.