To be honest I'd just stick with my wide diamond. I'm not too bothered about countering opposition formations and would much rather stick to my own. Furthermore, I don't have enough MCs to be able to flood the midfield like I suggested. If I HAD to switch to another formation to counter a wide diamond with my current team and the positions I have available, I'd either go 4-1-3W-1-1 or 4-1-4-1. I've heard 4-5-1 V also works well.