In addition to the newly-returned British Airways, you can earn and spend Avios on flights to/from Malta, via budget carrier Vueling.
Vueling flies a limited service from Malta, but to two very attractive destinations – Barcelona and Madrid.
Note that Avios can only be spent on Vueling flights from an Iberia Plus account. However, you can easily transfer Avios (for free) from avios.com or your British Airways Executive Club account, by using the “Combine Your Avios” function.
You can sign up for an Iberia Plus account here.
With the above in mind, I’ll be focusing on any Avios earning options that are too good not to alert you to.
If you’re Malta-based, and unlikely to ever use Avios other than on Vueling flights to Spain, you may as well simply join Puntos. However, if you are likely to take BA etc flights, then Vueling offers another viable Avios collection/redemption option.