I think we should be able to go into debt (up to a limit) when bidding on players. I bookmarked a player early yesterday and was all set to target him today, but in between the economic update took place and I lost nearly 80k from my balance, so I'm not even going to get a chance to bid on him at his closing time. This is really frustrating, and I see no good reason for it.
I understand part of the restriction is probably to protect noobs from bidding insane amounts when they don't know any better and bankrupting their teams, but that shouldn't be a problem borne by the majority.
I'm skilled enough as a manager to look ahead at my schedule and see that I have a lot of home games coming, so I'm ok with going into debt. I also have two TV games coming up, and I'd be more than willing to go into debt adding a player if it would help me win those games.
Also, with the inflation the TL is expericiencing right now (most good players are listed for 300k (many far above that), compared with the much smaller amount of cash most teams are bringing in, I doubt most people can even bid on a quality player the day of the economic update. They probably have to wait until a home league or cup game in order to get enough cash flow.
In short, I think the decision to go into debt should be in the hands of the user. The more decisions you offer us within the game, the more strategy is involved, and the more in depth the game will be because of it.