There are a couple of aftermarket parts I would highly recommend. They are not expensive either. First is the extended magazine release. They are available from many makers. it allows a much easier and convenient release.
Second is the auto bolt release. If you have the bolt in the held back position, this piece allows you to release the bolt by just pulling it back and letting it go forward. Otherwise, you have to pull it back and manipulate the slightly awkward bolt release.
The above two are for convenience. For performance, I recommend, at the least, replacing the factory hammer with a drop in Volquartsen replacement. Makes a huge difference in trigger pull and crispness.