You could lose your 5 athletics and 5 WM and throw some of it at STR to get another power strike, spend the rest on IF if youve got no where else to put it. You dont need athletics or WM, i have no athletics and can fight on foot just fine. Also about swords, cut damage really is just crap, and if you hit someone with alot of armor even if you have 10 PS its not going to do much, unless you just wanna kill archers i wouldn't use a sword, or atleast use a longsword. Also 1h cav is hard at first you gota stick with it if you actually wanna do 1h cav. If your using a 1h it doesnt matter if you cant thrust, when fighting other cav you should t bone them and spam the shit out of them they got a lance they cant hit you back.
Having no athletics can be fine when you get in a fight after being dismounted, but you will be next to useless in maps where you can't use your horse. On top of that, if you survive a bit after being dismounted, that 0 athletics will get you overwhelmed fairly quickly, as you can't prevent anyone from circling you by backpeddaling.
The longsword get's a rather large (30% I think) damage penalty when used with a shield, making it's effective damage much lower than that of an arabian cav sword or a nordic champion's sword. The speedbonus from being on horseback also increase your damage substantially. You won't be killing tincans in 1 hit, but I've yet to see one survive 3 hits with good speedbonus.
On foot it will take a few hits to kill one, but with my 18/18 build I can kill them just fine.
The use of thrusting as a 1h/cav player on horseback is not for fights against lancers, it's to kill other 1h/cav. The reach on the stab is quite long and you can often kill the enemy bfore they can reach you with their swing. When using a long espada, you can use the thrust to do high damage stabs against tincan infantry.