Well decided to fill in this thingy correctly to help ya out.
Used to play Bicheon/Lightning/Cold on Titan.
-What are the pros?-Some people would say that it's not a pro at all because you can buy potions. But still, speed and dash is kinda cool. Speed buff saves money and dash saves you in some situations.
-Magic damage increase buff ofc. I was leveling 2 nukes both lightning and cold just skilled shouts. Actually it was 3 skills, two cold nukes and the lightning one. So that buff increased both cold and lightning nukes, while if you are a fire nuker you do have only one decent nuke.
-What are the cons?-Immune for sure and a slightly weaker imbue, which is not really that true because imbues also magic based and that piercing force series increases its damage aswell.
-What are your masteries ( example: fire/light/ice )-Been told, Bicheon/Lightning/Cold
-What is your level?-65, but not leveling it anymore.
-How do you do in PVP?-It was okay, since I had a decent shield and all my gear was fully blued (100% int, str and those other blablas), I had no trouble killing off people. Cold nukes helped me on those levels, because people weren't just fully resisted against slow effects. After that I just pewpewed them with my sword skills.
-How do you do in PVE?-Fast. I had always enough money to buy potions. I really really don't agree with those who say that you should just level one nuke. Okay if you are using shouts you have 1,5 nuke, because shouts are weaker than a normal nuke. I just used Snow Storm - Ice rain as a starter skill and Tiger's Thunderbolt to finish them off. At level 54 I was already leveling at Yetis and had no problem to kill them off with two nukes and since both of those spells are some kind of an AOE I could kill 3 of them with one pull. If you are in trouble all you have to do is to pop your snow shield and if you are in deep shi' you just use your ironwall shield and there you go.
Of course I do not have as much experience as a level 100+ player, but I don't think you should just throw away lightning and all those fancy stuff just because of being resisted against statuses and the stronger nuke.