Well, let me explain why I think it's a mess and why "time travel" is a risky plot device. If Eddie Thawne dying means that Eobard Thawne never existed. That means that Eobard never came back in time and never caused the explosion at the particle accelerator 20 years early and therefore Barry would NOT be the flash yet! Also Barry's mum should miraculously be alive again, his dad should be out of prison and then Eddie would never learn that any of this had happened (because it hadn't) and therefore wouldn't kill himself and so Eobard would then exist again and everything would happen all over again and then Eddie would kill himself and OMG we're in a timeloop!!!