Matraville is becoming a better area. Still heaps of housing commission so best to drive out there to check out the location of any properties for sale. As a rough guide, the closer to the coast, the more housing commission. Close to Anzac Pd is a bit scary, there are security guards at the bus stop in the evenings. But the other end of Matraville is very nice. Also show a bit of caution on the Matraville/Hillsdale border too, lots of housing commission there too.
Prices have gone up a lot recently as Maroubra, Pagewood and Little Bay are becoming unaffordable. 4 years ago we were looking at semis around the 500-550K mark and those prices are long gone now.
The area near the shops is definitely the more desirable part of Matraville and with the large blocks there is potential to put in duplexes or even townhouses.