That's 3 games a Division. So 12 games in total. Or 24 hours of football (inc the breaks!). Over a weekend, at one venue with a couple of pitches, that's just about doable.
However, what's the point?
I guess some people like play-offs (finals-footie, as that annoying bloke on Fox Sports keeps advertising!) and some don't. For me, whoever wins D1A over the next couple of weeks shouldn't then have to turn up at Burton - or anywhere else - to win the title. They won it over the previous 18-games home and away
If D2A play-offs were used to decide who got promoted, then you'd potentially have the forth placed team going into D1A the following season and in all likelihood getting spanked every week. So I can't see the point in having "playoffs" if promotion is decided over the previous 18 games. UK-Championship the first two go up, then there's a playoff for the third place ... There's a little bit more sense to that type of system (but I still don't fancy it).
And there is no promotion from D3 or D4, so what's the point of playoffs for them?
You got your league season, home and away, to decide who is the best team over the season ... and you got your cup competition to decide who is the best at 1v1s (and who gets the luck of the draw, the best ref decisions and so on).
Can't see the point in a finals day that serves no purpose. Don't want to see a league competition be decided by one or two one-off games.