The problem with voting for a party and not a candidate, is that the party machine will fill the positions with those on side to the leadership’s regime at the point in time when such a voting system was implemented.
Take it back a few years and Blair would simply fill the seats with hundreds of his cronies, 200 odd little Blair/Mandleson clones 
, and depending on which pointless leader the tories had ruining the ship at the time, would see hundreds of Majorets or hundreds more Cameron cohorts from Oxbridge or the Cotwolds croquet/polo lawns, and as Cameron was a Blair disciple the country would permanently become a Blair regime dynasty, with no way of getting rid of them, difficult enough its proving anway, what with the quality of the leaderships that have followed.
I think most people try to vote for a party, and that has produced the dozens of tories currently half in half out of parliament who don’t have a conservative bone in their body, and the same on the Labour side, where a sizeable proportion of the tribal working class parts of the country are represented by someone who hasn’t a clue about what matters to the working class of the country.
The Liberal Democrats, once again proving to even the most blinkered they have neither of those attributes, i really don’t know what their voters are on.
Even those who vote for a person rather than a party have had their choices dictated by either tory or labour central offices who parachute in their choices, overriding the wishes of the local associations.
I’m fortunate enough to have a decent genuine Brexiteer as my MP, one of that handful who refused to vote for May’s surrender document at the third vote, yes he’s a tory but because he’s a genuine conservative not a wind blown candle i owe him my vote…however from what i read Johnson has issued the threat that those who don’t vote for his new deal (possibly May’s surrender treaty with the Irish backstop reworded) will have the whip withdrawn, in which case all bets are off re my voting intention, if they replace my MP with another yes person for the next election then TBP it will be…if my MP stays then i doubt if TBP will stand a candidate against him because it would be utter folly, shooting themselves in the foot labour style.