I'm planning on going for 10 days, last group game and some knockouts. I've had no luck on the lottery but have bought a few tickets on the FIFA resale platform for a small amount higher than face value. Everything is so expensive though, even face value tickets are crazily high vs previous tournaments. FIFA's greed is off the scale.
I also have England membership and have built up caps so hope to get some tickets from the FA.
The general principle for this World Cup is not availability of tickets but more how much you are prepared to pay.