When I was training to get a 210kg bench (which was a jr aus record...so I know how to bench lol) - I was training bench 3-4 x a week and doing direct tricep and rear delt work 3 times a week.....these programs were fairly advanced I must admit...variations of russian style weight lifting plans and diff sheiko programs...
WS4SB is great for athletes....I would not suggest this program unless your training for sport....
Focus on a goal...work towards that goal with the right programing and achieve that goal, then move onto the next goal...dont have 2,3,4 diff goals at once because you will get nowhere....
Also getting a 100kg bench should only really take you 2-3 months, if that...unless you bench is like 20kg atm...but id say youd be able to bench 60kg??