I just pulled 4* Ant-man, i guess i am one of few players who is actually happy about that

Why you ask, well it is because he is the 3rd wheel to complete my 4* Quantum Trinity of Ghost, Wasp and Ant-man. I have only been playing for a few months so the added 25% attack at the start of the fight for each hero should really help me out. I am wondering if it is a good idea to add 3* Hood to that team so Ghost gains the benefits of her synergy with Hood as well.
I really love playing Wasp as well as Ghost. Comments on Ant-man would suggest he is only a synergy partner and a 3* Hood will probably turn out to be the same. So is adding Hood worth having 2 'dead' spots on a team?
On a side note: What does '25% attack at the start of the fight' actually mean? Is it limited to a few seconds (start of the fight) or does it last the entire fight?
On another side note: Is there a way to see/check what synergy buffs actually do for the numbers of my champ before i start a fight?