I think it's the right way to go ; the yearly season model just does dwindle the player base. Still I have a bitter taste i my mouth when I think of the 165€ I cashed in for the LEP, when I could have got Horizons and be good until Q4 2018 - at the very least. When I bought LEP in August 2015, the (10y)plan was one extension per year, and even then the added-value of the LEP was a gamble : it would be covered after about three extensions/seasons. Now we know that Horizons lasts for three years... FDev should really seriously consider some perks, or partial refunds by now.
I have the same feeling of what you said here. When I bought LEP, the idea that I had was a 10 years development plans, 1 expansion per year. Now we know the development is gonna end at 2022, that's an 8 years plan, with season 2 spanning 3 years. By calculation, the LEP is more expensive. Personally, with this information at hand, I do feel it was a bad investment. If I have known, I would have bought each expansion during discount offers.
Although, I don't regret it to the point I'm disappointed. Elite Dangerous has been a fantastic experience. If FD needs to reroute their plan to extend the game's development longevity, I'm fully on board. I'm also glad to hear about premium contents for LEP owners. Hopefully, there are more to come. I just can't help feeling, based on my earlier assumption, I am now with an investment loss. It would take time to come to terms with it. Since this is my first LEP, ED is now a lesson of a need for careful decision before buying one.