Strange planets can be very small.
How big could a planet made of strange matter with 1g be? It might be less than a pea. Strange matter is dense.
Searching For Strange Quark Planets
It is interesting to note that, under the SQM hypothesis, quark matter
is bounded by strong interaction but not gravity. So, SQM can even
exist stably in the form of small chunks in the universe. It implies
that planets composed of strange quark matter can also exist stably
8,9. Strange quark planets are very different from normal planets.
They have a much higher mean density and a much smaller radius, which
provide us with some effective new methods to test the SQM
hypothesis... For a strange quark planet, its mean density can be
as high as 4 × 10^14 g cm−3...
I calculated here that a strange quark matter planet with density 4 * 10 ^5 would have a surface gravity of 1.14g and a radius of 0.1 km. That is a surface area of 33 acres. I take away that a strange matter planet can be pretty much any size desired.
The main point of the linked article is that such planets are so dense they can orbit very close to their parent strange quark star - closer than planets made of normal matter. You can put it as close as it needs to be to keep warm which might be very close.
Strange quark stars are like neutron stars in that they kick out most of their energy as Xrays. I here propose that your habitable strange matter planet has an atmosphere (by definition) and just like Earth, that xray-opaque atmosphere will soak up the xrays. The energy from the xrays will be re-emitted as visible light. The heat source will be the glowing sky.
Possibly, if this scenario is not wild enough yet, the strange matter planet can be tidally locked to its sun. Then the planet can serve as a barrier to prevent persons on the dark side from being radiated. No radiation will penetrate the superdense strange matter planet.