Part of the problem is that you want a better 'bench', and you're trying to improve it by training 'chest'. If you want a good bench then you have to train your bench, not your chest.
The bench is about much more than just pecs. The bench is triceps, delts, lats, AND pecs.
I'll just quickly run through what muscles are used when you do a rep.
All the way through the movement your delts are stabilising the weight. Once you've brought the bar down to your chest the lats explode the bar off of the chest and the delts do a lot at the bottom of the movement also. After your lats get the bar off your chest your pecs and triceps keep the bar moving. After you get about half way your triceps start taking over and finish the lift.
You need to train lats in the same range of motion as benching (bentover rows etc.) You need to do heavy close-grip benching for your triceps. You need to work the explosion off of the chest with bottom position work and floor presses, you need to work the end of the rep with heavy lockouts or by the use of bands etc.