i'm a student, and for me, $70 are very much money. And since the upgrade from ST3 to ST4 is a paid upgrade, i don't think i will buy a license for ST2/ST3, just to pay again after some time.
But i thin that ST2 is a great piece of software, and i want to honor it, that i am using it every day. So i have a dilemma.
I don't know how much the paid upgrade from ST3 to ST4 will be, and when it will come, but i assume that there are two years between each paid upgrades? That would be $70/24 Months = $1.6xxx per month.
And i am able to pay $1.6 per month. So i was wondering if you could maybe offer some kind of subscription model, so that every subscriber pays $1.6 per month, and gets full access to ST2 and free upgrades, as long as he is paying for his subscription? The benefits for yourself would be a regular income and paying customers who think that $70 in one piece is too expensive, and the benefits for your customers would be that they honor your work and have a price model that is not too expensive for the moment.
Just think about it...