Any one got any tips for this issue?

I don't think the electric rake has been boosted, Did you go into sandbox mode and level up a few times before going and fighting psychos in the story? As you level up your attack gets stronger. Weapons do much more damage the higher your attack skill is.

they did change the way you damage psychos. The first blow can deal great damage but second and third are very slight if you're using the same weapon. I think it's best to wack 'em, retreat a sec or two then wack em again. anyone else notice this?

Also I think the electric rake has been boosted. I don't remember it dealing so much damage in DR2. I hit the first psycho in the game with it and was amazed, It took away maybe a third of his health. i may be wrong though.

Anything different from dr2 that I should know?

Learn the combo weapons and abuse them. Make the spike bat every time you leave the safe room for instance, it does great damage to psychos and the power attack one shots zombies, so it's an all purpose weapon. The combo weapons get you tons of PP and are
just great in general.

Thanks for the tips my fellow cleaners, i will try some of your solutions and see what works best.