Balancing discipline vs. improving results?

I was thinking long and hard about why I didn't make the previous 5-6 years I attempted to trade discretionary. I made all the common mistakes, not following my plan, general inconsistency, quitting for the day after just one loss. You get the point. So I defining how I will be successful this time and a dilemma came to mind.

For those of you successful, or think you have the answer, how do you stay consistent with your trading plan, but at the same time look to enhance it. I am amazed by traders that can watch and be impressed by other traders and their methodologies and then just ignore them and trade their plan. How does one do that?

Me, I am easily influenced, and I had a great plan for trading with just price, volume, S/R and then I am introduced to market profile and I think what a great way to augment my plan. Both methods are volume based, etc. Pretty soon I had done this so many times I no longer had any plan just a bunch of flash of the pan ideas. Whichever one looked the best that day that's what I did. It's obvious why I failed.

So how do you balance sticking to your plan while at the same time attempting to improve your results? The markets aren't stagnant, things have definitely changed with HFT so how could one even have a trading plan the same as pre HFT or any other major market change and expect that trading plan to still work?

My plan for now is to automate and keep myself busy so I can't dink with the strategy. Just brief checks to make sure trades are firing correct, etc.