well, giving it a few runs, i can do off element if i'm packing enough HP and got some help.... wouldn't even try off element with no less than 9k HP per character.... cause those double/triple hits hurt bad (which is why my light team can live for a while with Sol and chaos magic). still gotta admit fire is better trying them out... but brynhildr being my only healer always puts me on a damage race situation, which i can lose if RNG wants to target her with attacks...
also, some R hime actually come with some good effects... less damage you deal, but some have a self damage cut and one comes with b frame buffs... (too bad konohana can't debuff well cause she has sniper shot level debuffing). for a free player not packing much kami, even some R girls can help save their life
in fact, one of them gives 35 burst to a single target... helping those with a shingen strategy....
do you mean solo or with help? cause my light team can at least last long enough with 3-4 players as backup....
and my fire comp lets me push a lot of damage out (joan, ares, brynhildr, agni, svarog)
that, and i honestly have more fire element skills in my grid than that...
if it's a grid full of weapons with 2 effects, then you can have 20....
and personally, that's what i'd aim for cause it guarantees 100% to HP and atk when it's all at skill lv 20
still would hopefully be more assault oriented, but doubled HP and atk still sounds really good