So no-one ever encountered this problem?
No, never heard of this one. Can't find other examples with a web search either. Really don't know what this is.
The battery life is a real suck! After Nokia e90 this HTC is the purest shti to someone who tries to work using telephone.
Those old Nokias had battery life that exceeds any modern smartphone. But what sort of battery life are you getting, and for what sort of usage (time with screen on, time in call, what you do when the screen is on, what apps do you have syncing in the background and how often)? It may be that there are things you can do to improve battery life (obvious ones include not letting every app poll for updates every few minutes, for example). A battery monitor like GSam Battery Monitor can help identify what is using the power.
Touchscreen jams once and a while so nothing happens.
Again, something I've never experienced. Are you running anything in particular when it happens?
The predictive text input is THE S H I T of all modern times! It is disabled, and the f*ck still insert its idiotic words to any application that requires typing.
There is NO WAY to get rid of the prediction shit.
Really? I just tried switching to the stock HTC keyboard on mine (what I guess you are using) and disabling predictions, and they were disabled. No problem. Are you using the "trace keyboard"? I believe that doesn't let you turn off predictions (it is hard to see how swiping around rather than pressing keys would work without prediction), so if you have that enabled you need to turn it off.
Otherwise what software version are you running, and what keyboard are you using?
I really really really miss the times when Symbian was the king, and phones had batteries lasting a full work day, or even 2, and they had REAL buttons to type a message in a few seconds; a message that contained the words YOU wished to say, and not the words the shit itself decided to enter.
You can install other keyboards, and maybe a different one will suit you better.
Nothing to be done about the buttons, unless you buy a Blackberry. In the early days a number of manufacturers, including HTC, made Android handsets with keyboards. The lack of them now is because there wasn't enough demand for them to be profitable (which is no consolation if you are one of those who wants one - there are a few trends in current phones which I dislike too). Maybe fashions will change, but right now nobody is making them.
But you have enough odd things going on (the "invalid input" thing, the touchscreen freezes, and maybe the keyboard predictions) that I wonder whether it's worth considering a factory reset (after backing up important data)? If the problems are due to something you installed, a messed-up setting or a corrupted cache after a software update that would fix it, though it's a scattergun rather than a surgical solution, and it's not a guaranteed fix since we don't know the causes.