Well, you could in effect raise the minimum bid required, see here - http://www.wpauctions.com/minimum-bid-increment/
- but it would be a manual process and would affect ALL your auctions.
There isn't a feature yet to allow this on a per auction basis. So if you have 10 auctions then all 10 auctions will require a minimum bid of $35 as the next bid, as per your example.
Yes, the above features are in the Pro and Pro Plus versions.
Hope that helps.