To evaluate Sobers the allrounder, one has to understand Sobers the player.
It may seem ludicrous to suggest so but much like Viv, Sobers did not work at his game much and if he had a hardnosed professional attitude like say Alan Border, then he would've easily avereaged 60+ with the bat and less than 30 with the ball.
When on tour, Sober's normal routine was to hit the bottle and hump a chick till the wee hours of the morning, have a cold shower and appear on the field.
Sobers was not interested unless it was crunch time and which is why he could elavate his game a lot in pressure situations ( witness for eg how many times Sobers forged partnerships with Kanhai when everyone else crumbled). His record versus NZ was indicative of that - NZ were, by some distance, the worst team of Sober's time and he couldnt be arsed to perform - the only time he did, his team badly needed him to.
His bowling is very reflective of this : his pace bowling was worldclass - Boycott is on record saying that Sobers weilding the new ball is not a comforting sight since he could make the new ball talk like crazy.
Too often on pace-friendly wickets he'd open the bowling or bowl first change, grab 2-20 and then let Griffiths or Hall or Gillchrist finish up the rest.
On spin friendly wickets, he'd let Gibbs/Valentine/Ramadhin get on with the business and only bowl short spells.
He only bowled long spells on flat wickets because Sobers as a spinner did not have much variety or turn but had beautiful loop and he'd bowl a lot giving the rest of the bowling lineup a breather.
This is what makes Sober's bowling suffer but a few times he rolled up his sleeve, he bowled brilliantly.
For eg, in Edgbaston 63, he took 5-60 while removing Mickey Stewart, Barrington, Brian Close and Ted Dexter.
In Brisbane 69, he got rid of Keith Stackpole,Redpath,Ian Chappell and Barry Jarman en route for 6-73.
In Melbourne 61, he scalped Bob Simpson, McDonald, Ron Harvey and Alan davidson en route to 5-120.
Add on top of that Sobers was a brilliant fielder and one of the safest catching hands in the history of cricket.
To get a better picture of Sobers, think of a person who can bat like Brian Lara, bowl pace like Chaminda Vaas, spin like Giles, field like Ponting and catch like Mark Waugh.
Then you'd have Sobers.