Chip why don't you try studying something in DR?, some extracurricular activities that will allow you to speak abundantly and get you in contact with Dominicans who speak properly.
The only way I can take classes at the university is to enroll full time and worse if I want to focus on Spanish I have to work towards getting a degree in Spanish for the purpose of teaching... get that a gringo teaching Spanish in the DR, haha.
As far as speaking faster, no doubt I was nervious and had to do about 20 takes and therefore was more deliberate than normal. As I'm never in front of the camera no doubt my English would be as deliberate as well.
Also, I don't believe Dominicans have a problem understanding me for the most part or are maybe somewhat put off if I speak slower, rather I would like to increase my grammar and diminish my accent to the most minimal level as possible. As it is now, I speak a somewhat simple type of Spanish and rarely if ever "guess" as to how something should be said if at all possible; if I'm not 95% sure of how to describe something at any given moment I will use other words to get my point across correctly.
My goal for speaking would not necessarily to mimic Dominicans but the generic form of Spanish one sees a lot on CNN in Espa?ol(my favorite Spanish channel), some of them speak such pretty Spanish too, without real strong accents one way or the other, at least from my point of view.