I don't mind it. It's an infill development replacing a derelict garage. From the renders it looks as though the fenestration will match up to the existing terrace (which is more than can be said about the extension on the Blind Institute in Newport Rd) and it will extend that block in a similar style albeit with a few modern flourishes.
The terrace that this development adjoins is lovely and I'm glad the proposal is not something showy and overpowering. Directly to the north is a three storey block of pebble dashed flats of the most uninspiring design. A cutting edge building here would look incongruous in my opinion. Also the point about the value that the flats would go for given it's location is a good one - that must have affected the design process.
Sometimes less is more. This development will win no prizes but I don't think it's awful, it will link the Bay and Butetown and will add a bit of bulk to a currently derelict site.