[Q] To root or not to root?

Have an old P7500 wifi on 4.04 (from the OTA). I only use it for internet browsing, gmail, google drive, youtube, and VLC. I'm new to this whole custom rom / rooting thing, so go easy. :)

My questions are: Would there be any advantage to my installing a custom ROM (for what I use the tablet for)? Will I see any significant gains in app speed, or videos? Do people often"overclock" this tablet to achieve a gain?

From what I've read, the "OMNI" rom seems to be considered simple and smooth. Not as much documentation on initial install for a n00b tho! I see this post, but it isn't readily apparent at what stage I "backup" my original files.

Thanks.