The 28-90 is particularly
poor at 28mm. I wouldn't touch it. I think the best value/quality compromise in this area at the moment are the Tokina 19-35 - available for about £170 or the Tamron 19-35mm at around £180, including lens hood.
At this price, you will have some distortion, and some softness wide open, but within acceptable limits - going as wide as 19mm is a real benefit on "cropped" DSLRs - after all 28mm is pretty close to a standard lens field of view (44mm) on the D30.
If at a later stage you feel the need to fill the 35-70 gap, you have a number of lenses in the 28-70mm range to choose from, or save some money and buy the 50mm 1.8 and take a few extra steps
(that's what I did).
Alternatively, get a used fixed focal length as an interim measure - a quick check on Jessops shows a surfiet of Canon 28mm f2.8 lenses - should be available at a keen price.
Colin K. Work, Pixstel