Factory reset vs. recovery mode (hard reset)

My Google Nexus 7 tablet is running Android version 5.1.1 - the latest the hardware will accept. At times, the device is sluggish and Chrome, Firefox, and the Settings panel occasionally crash, even after a full charge. I have removed every app not in use and driven down the cache. Currently, the internal storage is showing 16.40 GB free out of a total of 27.56 GB. The tablet otherwise functions well.

I have seen advice on various sites (including androidpit) about resetting by performing a factory reset or using the recovery mode. Everything of importance is stored elsewhere, so a complete erasure is of no concern. What is unclear is whether I would see a performance from either of these procedures.

Any advice, including potential downsides, would be appreciated.

Thank you. Do recommend the hard reset (recovery mode) over the factory reset?

Thank you. As I mentioned in my initial post, everything of importance is stored elsewhere.

I have a follow-up question. You advised a hard reset (recovery mode) over the factory reset. In addition to the repair of "bugs (after an update) and improve[d] ... overall performance" you mentioned, what is the difference between the two procedures? Why is the hard reset preferable?

Thank you.