I live in Sweden, really crappy for growing peppers to begin with, but with some care and love it works fine.
I do as you, pre-grow the plants indoor during the first months of the year, and then when the summer comes (if it comes to sweden) I set out my pots.
All peppers are plants you can have several years, it is just a mather of space and light.
I cut my plants down to smaller sizes and re-pots them into 3-4l pots so they do not take so much space duing the winter.
Don't need so much light and heat during the hibernation either.
I only have 6 plants currently, in a space of a eu pallet.
Fun (and hello)! I'm also a Swede struggling with Sweden's lack of proper hospitality towards peppers. This country does not like them very much at all. Lucky them that they have humans who care way too much about them to let them succumb.
I would like to echo this overwintering ability, especially for people who live in climates where the summers can be ridiculously short (such as Nordic countries) for getting a seed up to a productive plant. It can decrease the frustration of bringing the plant up-to-speed quite a bit, since you start the grow season not from seed but a thick stem and root system. I would like to be clear though: It's not hibernation since Capsicum can't hibernate. All we're doing is tricking the plant to survive on a small dose of light with minimal growth so it does not kill itself by expecting a lot of light for an abundance of leaves, and barely getting any.
Re-potting can also be useful for other purposes than taking up space. When you overwinter very little transpiration is actually occurring. Water is barely moving through the stem and evaporating of the few leaves we leave. Therefore, with too much roots there's an issue of overwatering and rot. The trick is to water in proportion to the light and try to match the leaves and roots after that which is available. Usually not a problem though, not for me at least, but if you're really cutting down your plant a lot and you care about it greatly it might be worth it to give it a little trim job down below.
Finally there's another trick: Artificial lighting. A small LED light does not cost much and can improve your success with overwintering drastically if light gets really scarce. Seriously, you can increase the local flux 3-4 times relatively easy with a weak light by showing it really close.