*I don't know if this has already been discussed, but I didn't find anything too specific on the forums/wiki*
I would just like to ask: can the shied regeneration boost of the Seraphic Aura be useful? Or is it just barely noticeable?
Does it only affect the speed at which the bar refills, or also the time that the shied takes to start recharging after an attack?
Is this ultimate a valid choice, or is the Valkirian Aura just simply better?
(Also sorry for my bad English *cough*)
Your English is quite good, but sprite ultimate questions have been discussed pretty heavily. Try a Google search such as seraphic aura site:forums.spiralknights.com. Many threads address the question of Seraphic vs. Valkyrian. Probably some of them address the shield regeneration of Seraphic specifically. If not, try asking again here.