1) Attitude problem;
2) Rank problem (ie. she demanded at least a baronet);
3) Money problem. Depending on the interpretation, which has been mentioned by others in this thread, her dowry may be only 1/3 of 10,000 pounds. Personally, I'm in that camp. But regardless of whether that number was satisfactory, a prospective suitor would probably figure out pretty fast that there was a spending-happy baronet involved and he may be asking for money in the future; and
4) If I recall, the number of women was greater than the number of men at the time, so if a man rejected Elizabeth he had other options.