After graduating from UCD, I did an unofficial post-bacc through UCD Extension using their open campus program.
Pros:
1) Stayed in Davis, and continued to do research at UCDSOM.
2) Familiar with classes, environment, and professors.
3) Didn't have to move.
Cons:
1) Registration sucked. Was last priority....freshman had higher priority than me. Professors had to sign a sheet to let you in, and some classes (engineering) required a signature from the dept. chair.
2) Processing of your class sucks too. If your class has online resources (e.g.: lecture PDFs, online quizzes), then if there is any delay with Extension's processing, you could have many issues.
3) Not on email list. Since one normally loses their school email after graduating, and for reasons stated in #2, you are usually not on the class email list, so you may not receive important information. You can remedy this by having the professor manually add your email. I lucked out, since I worked for UCDSOM, i still retained the my UCD email.
4) Costs. It costs an arm and a leg to do open campus through Extension. You will essentially pay 50%+ more than an undergrad if you choose to go full time (12 units). So now you will have to weigh the costs, and the yield. If you just take 2 classes at a time, and get a 4.0, it won't look nearly as good as taking a full-time load and getting a 4.0. But that costs a lot.
In my opinion, if you don't have any other choice, you can suck it up and do it. I did it for 1.5 years but said screw it and went to grad school at UCD. Although it was quite a hassel, I did get into all the classes I wanted (biomedical engineering). Some classes (engineering classes), I had to wait 1-2 weeks before the professor let me in. For grad school, I am currently able to enroll in upper division undergrad courses as electives. These are still considered "post-bacc". Therefore I'm essentially doing both a PhD, and a post-bacc program😉, and get to do it for free. In your case you may have a hard time with that due to a lower overall GPA. If i recall UC requires at least a 3.0 to even apply to grad school, and you will need to take the GRE. There are exceptions depending on the program, but thats something you will have to ask around at UCI. I had a sub-3.0 GPA, however had a 3.4 for post-bacc and a 36 on the MCAT (program chair made an exception to sub my MCAT for the GRE). So my graduate program gave me a conditional admission where I had to get atleast a 3.0 GPA when I started classes.
Personally you should address the low GPA over any other factor on your application. Any amount of research experience will pale in comparison to a low GPA. Recall that at UC's, you will be automatically rejected post-primary application due to the screening process (cut-off 3.0-3.2) regardless of GPA trends, and extracurriculars. MCAT and GPA are treated equally at UCs, and thus doing well in one does not make up for the other per se. If you can do an SMP, that would be great. Make sure it is well known (e.g.: at the schools you apply to). Otherwise, you may have to look into applying to a post-bacc program, or go through open campus.
