On hard mode a level 30 will do much more damage with the relic when fighting praetorians. They will also take less damage from enemies meaning there is less chance of the relic holder getting killed which can cause a wipe. Being a 31 (who still enjoys running the vog most weeks) I have a lot of experience holding the relic. However I don't often like to be the relic holder as I have a 331 gjallarhorn and black hammer. This makes me very VERY effecting at dealing damage to bosses and I often feel wasted just holding the shield up for my team.