Pending balance rule seems to be only for ebay sellers and to get away from it is to make buyers drop a feedback about the seller. How about for subscription type only? I cannot let users view my posts if their payment has not cleared yet. Technically, the IPN should have payment_status var sent after the buyer has paid for subscription but in my case, I only get it on the first IPN message which has a "Pending" value and nothing on the second. This causes my handler to throw out an "Unknown payment status" error.
Actually paypal does have a pending payment type for subscriptions. One more reason not to deal with Paypal.
The trouble you run into is that some transactions will not clear, sometimes a paypal account is new, foreign transactions also fall under pending.
The worst part about paypal subscriptions is that there is no real upgrade path, you could use recurring payment profiles instead of subscriptions, but those also have a limit for upgrades and downgrades.
If you can afford to get a real merchant account, do so.