Keep selling and they'll go away on their own. 21 day payment holds are usually gone by 90 days of selling, category restrictions usually start falling off no later than 6 months after you start selling.
Limits are there to make the eBay and PayPal community safe --- this what they say
Just sell slowly and steady - you'll somewhat 'raise' your selling limits, but definitely not able to remove them. Good Luck!
new ebay seller 
