A lot of good opinions in here.
One other consideration:
My experience has been that north of Monterey Blvd. tends to be more desirable from a buyer's perspective, so that would make it better from a seller's perspective also. Sunnyside is very block to block in terms of desirability, so cruising around to see how they compare is the best advise. Generally, the closer you get to Glen Park, the better and if you can find a home that has something to it, such as a view, garden, or architectural style is what will set you apart from other listings.
If you are looking in Bernal too, the same issues apply in terms of desirability: i.e. North of Cortland is generally better than South of Cortland. So, if your budget dictates South of Cortland, the same issues apply in terms of view, garden, architectural style, etc... to set you apart from other listings.
Best of luck.