There are al lot of topics about repairing bootlopping, bricked, etc. devices with most often solutions in different threads. But off course you read mostly about problems in those topics which could blur an objective view. But I pre-informed myself a bit before rooting. Off course there is always a risk, but I think the changes on failure are very very slim. If you read and follow nstructions carefully and understand what you're doing. Also about how to do there are great instruction videos.
Main questions: do I need root, do I understand instructions and is it worth the risk (perhaps losing waranty)? I for myself can not have Android anymore without root and rather buy a new Nexus in worst case scenario. Need it for Ad Away, Greenify, Titanium Backup, OTG read and write, Power Toggles, ES Root Explorer, Xposed with Gravitybox and Xtheme Engine, etc.