Suggested

KERS limit

Can it be implimented that there is a 7 seconds per lap limit on KERS deployment? It’s so unrealistic that you can burn all your KERS on a single lap. It sometimes make mid race tactical use pointless, when others just wait until last lap and go 10 seconds faster. If we are looking for more realism, this is definitely something to consider.

So, what is unrealistic? We have some extra energy (KERS works in another way) that can be used during the race and you decide when to use it. If someone has lots of energy and you don't, it's either your energy saving strategy is wrong or your car is simply not enough developed. Everything is fair!
And I like setting fastest laps when can't reach frontrunners.

Your idea contradicts with what you are saying, "people are using all of their kers on the last lap, so lets give them more kers overall and every lap so that managers have to hold the kers button all the time". I don't even want to think about what auto-kers would like with this implemented. This is not strategy but just a distraction from the real strategic decisions we make during races. It is not quicker to use all of your kers at the end of races because this prevents you from taking advantage of drs from opponents and potentially backmarkers as well. If you watched a top level league race you would never see this, I promise :)

You mis-understand me. I would like a limit to the amount of KERS that can be used on a single lap, just like in F1.

I don't think I misunderstood :)
You specifically asked for a 7 second KERS limit per lap, and I directly explained why this would do the opposite of what you want. Also, F1 doesn't use KERS anymore they use ERS and that is not rechargeable.