I heard...er read that... Dracomic!!!
Now integration issues. Thunderbolt and his sister are important to the future...in some unspecified way. Is there a 'Villain' time traveler who is from the ...not so distant future who is interested in changing the present to proceed along course that will change his past...our present in some fashion?
This 'Time Traveler' is not interested in killing Thunderbolt or his sister - far from it, but making sure Thunderbolt does actions that will lead to the future 'his present' that is more desirable to him. It seems as if Thunderbolt and his sister are going to be in some pivotal role in the future. Indeed Thunderbolt will potentially gain the power and recognition similar to 'Magneto' in his ...development as a hero {though not the villain status... which is my plan, at least}. This 'Villain' would by necessity be powerful...but not really 'known' as a time-traveler' it would defeat the purpose of his deeds here in our present. Though he is known to make remarks when he has been seen in action like - "So that's how that happened!", "...just as scripted.", or more often than not in the case of Thunderbolt, "...you were not supposed to be here ...this changes everything!" I say 'Villain as he may seem as such to outside observers but his motivations are a mystery to all... some times he helps the heroes...and sometimes he helps the villains make good their escape...no one really knows what he's after.
I do not know if you have a villain to match such motivations or capabilities. So I'd like to integrate Thunderbolt into the future...not necessarily the past... he is new to the superhero world and still has much growing up to do.
Also on non-heroic actions, as I said...Thunderbolt has a harsh but fair hand. Villains and criminals who employ lethal force or are known to have murdered people can expect him to pull no punches in apprehending them, as would any police officer - though his expressed intention is NOT to kill them...but he cares little if they are seriously injured in his taking them down. You petty criminals - thieves, muggers, or just violent bullies can expect a more 'gentle' hand but he will not hold back from bringing them to justice.
One case in point...
Thunderbolt's sister knows he has weird electrical powers she saw them when they escaped the junk-yard at the advent of of their powers...whatever her's may be, but she has never seen Thunderbolt in action and has not quite put two and two together to figure it out, but that will change I expect {despite her deliquent and rebellious attitudes... Sarah is very smart... in-fact she is smarter than her big brother... INT 16. She WILL figure it out - 'how many white-haired black men with lighting powers can their be anyways?'}. But one evening when Thunderbolt was out on patrol he spotted a group of young men chasing a young teenage black woman into an ally...obviously intent on having their way with her. He moved in from above to find the best way to get her out of harms way while he dealt with the potential rapists. Then he realized ...the young woman was his sister Sarah as the young men cornered her and one of them grabbed her tank top expecting to pull it off her. Shawn went into a rage... drew his katana and that young man will never touch any woman, against her will, with that hand again. Thunderbolt beat the tar out of those young men...but killed none of them...save lopping the hand off of one of them he turned them all over to the police ...though ALL of them went to the hospital first - some for longer stays than the rest. His sister fainted when coming down from above a man in a cloak and duster arcing lighting and yelling in fury laid into the attackers.
This is probabaly the most 'violent' Thunderbolt has ever been...he does not go out of his way to 'maim' but murderers and villains who threaten women with cruel or wicked delight... had better be wary of him... his hand is harsh sometimes.
It is my hope that the events of the game will allow him to grow out of his rage issues.