It's tough to say whether or not you have to adjust the sliders as only you can really tell whether or not the game is a fluke or if you are picking up the A.I. and the A.I. is just becoming too predictable in it's play. I haven't seen this from the CPU as in my most recent game the I got blown out by the Thunder as I was the Clippers. I've also had my share of blowouts in my favor. Anything is possible in reality but that Spurs game is probably an outlier in the normal distribution of outcomes, but you really have to play a large sample size to get a feel for the sliders as you can have an outlier that isn't truly representative of this slider set's normal distribution curve in your first few games. As far as the Knicks, that's a pretty realistic outcome IMO, I see the Nets and Knicks splitting the season series this year. I mean think about the Knicks, the Ball stops with Melo on the offensive end, either he is on or he is off, and when he is off they are very beatable.
The most important aspect of sliders IMO is gameplay, does it feel realistic, are you seeing things or animations that are not representative of real life. IMO with this slider set I'm seeing great gameplay, so sim stats likely will follow. Will every game's result be optimal in terms of sim stats, probably not, but then again what is sim? To get a definition of what is sim you have to calculate the expected team statistics for the Nets this year and there record, and then play a similar schedule to them and an adequate sample size to see if the stats you get from the game are close to your expected stats. I"m not a fan of all that, I just use the eye test and don't really care about the results because unless I have an exact calculated standard for what is sim, it's really not worth getting a case of slideritis.