Hi,
3x time width spacing for differential input pair is fine as long as your lines are not too big which should be the case for an 150 MHz application, via width is enough.
Cretu, are you doing common centroid structure at 5 GHz? Do you speak about circuit as LNA, PA, driver ...? Because if it's the case I'm really interesting in how you are doing your layout. I don't say that it doens't work but you certainly don't have the optimized extraction that you should look for ...
Again at high frequency keep your rf path as straight as possible. This is the best way to do layout at this frequencies.
sunjiao3, if you're design is sensitive to the offset you should use a common centroid structure, if not just do your layout straight and that should be fine.
Franck.