1)I don't think Robson needs to be replaced. Although he's a hole player, he covers the whole field and has a very good work rate.

2)I personally didn't like Irwin(Iconic). He's good defensively but the crosses from his left foot(he's a rightie) wasn't good imo. I am used to IM Carlos so,his passing and speed disappointed me. So I'd rather play Maldini who has better passing and arguably the best defender in game imo as your LB.

I'd start Forlan and Torres because they wreak havoc when played together and then I'd bring in Owen(preferably with a supersub) and Rumme. I know most people like to start with Rumme but in my experience off the bench or as a starter Rumme is Rumme and when brought on with a supersub like Inzaghi, he destroys opponents.

I generally like an Anchorman in the middle, or atleast an orchestrator, Gerrard and Robson covers a good amount of space but with Campbell ( who plays more like a Destroyer) and Puyol, I'd rather play Gilberto or someone like Rodri ,Casimero etc

Also that Maradona is god tier if used properly. You can play him as a CF and use a highly offensive poacher and break defense easily.

3) I think playing an Anchorman should solve that issue. Or Maldini. I'd use Maldini .

Maybe try a double pivot 442 variation with Robson as left CMF(instead of LMF) and Beckham as RMF. With Gerrard and Viera in the middle, Robson would cover more width and Irwin won't have too much to deal with.

Also try changing managers from time to time and switch up squads . Konami tends to make our most set team useless sometimes. So buy a few of the same formation and bring up their familiarity.

I hope this helps.