That's a good idea, in theory. I know a few folk who could make, say, 12 games a season, but no more.
The issue is, which pay at the gate prices do you pick, or would you take an average? Because depending how it worked, in terms of averages, it would possibly work out cheaper (for the fan, and worse for the club) to get that ticket, and only use it for the 'bigger team' games, and then paying as you went for St Mirren etc, as opposed to buying a season ticket.
Or is there a "standard price"? I genuinely don't know, as I've not paid in for years.