Best improvements to do to the DPLL SAT algorithm

Question

As part of a college class, I'm asked to improve the performance of a basic DPLL sat solver. I'm already provided a basic, slow working version (essentially the DPLL algorithm; furthermore, to select the next variable, it just loops an array and gets the next unused one). I have been reading papers on ways to improve it, but I'm a bit overwhelmed by the amount of optimizations one can do. I'm not looking to make an extremely efficient solver; just something that works better than a plain basic DPLL one. I have read about 2WL, VSIDS, and a handful more. Which optimizations will give me the most performance without overcomplicating things? The input with the most variables that I have to solve is of the order of 300, with 1500 clauses, if that is of any interest.

I apologize if something similar has been asked before, but I haven't found anything. I would appreciate any other tips if you guys have. Thank you.