The mental aspect of cricket is more important than technique and talent, IMO. You can have a very talented cricket with average technique (Dwayne Smith, the batsman) and a rubbish mental approach, and he likely will not be successful. Then there's the talented cricketer with excellent technique and a rubbish mental approach - Daren Ganga. Worth noting that Ganga has only started to have consistent success when he got his mental approach sorted, largely due to the maturing process he underwent as captain of Trinidad and Tobago.
Mindset is extremely important in cricket, as it entails (to a large extent) courage, application and self-belief. Nasser Hussain and Paul Collingwood are two players who come to mind who succeeded more so because of their mental strength than technique or talent. Certainly, neither were possessed earth-shattering talent.
You're asking to pick the more necessary of 2 aspects of the sport - talent and technique. I don't believe that either states rank higher than the other, as both can and do contribute to successful cricketers. But the mentality ranks higher than both, because you almost certainly will not see a successful cricketer with a rubbish mentality.