Most of the time none of those are doing anything. Shifting a manual is a minority of time, non-synchromesh makes shifting harder but it doesn't add much time. Most of the time when you stop the anti-lock brakes don't kick in and so again you lose nothing. TMPS makes your care safer if you have a lot tire - but tires these days are good enough that they rarely go flat. Same with the others - they are rarely used - not useless but only small factors taken all together - I've driven without each from time to time.