...They never would have gotten to war with the west (WW2) and would have been able to invade Soviet Union in 1939? Their army would have been equipped with obsolete tanks, they would lack experience, but Soviet Union would have been marginally weaker too and Germany could have used 100% of her forces against Soviet Union due to lack of 2 front war. Even many flak regiments could have been dispanded and sent to the front as Luftwaffe infantry, which would have had time to be trained as proper infantry unit, if that would have ever even been necessary!
I can`t say which one would have been better for them, either way there would be major weaknesses, but without war with the western nations(including Poland) Germany would have done more mistakes in eastern front where they could not afford it- expect without massive area to occupy they might have been able to afford it. And German tactics would have become as a surprise in 1939, historically Soviets had plan (that failed) to defend against German blitzkrieg, 3 lines of defense (strategically, tactically that would be thousands of lines) where first Germans would be slowed down, then halted and then driven back. Like in Kursk. But Germany may not have had experience in weaponry and/or tactics which not only managed to match extreme odds, but also to beat them. Becouse on paper Germany should have lost in 1939, already at 2 front war, smaller numbers and worse tanks, and only experience and time could improve that, their aggressive doctorine based on suprise + concentration of forces could only take them so far...
Well, i think nothing what i just said came as suprise to most of you, so i am just going to stop repeating not only myself but to many documentaries about WW2

So, would Germany have done better in WW2 without early wars against Poland and France? Without those wars, Tiger tanks would not have been developed (at least as early as they were) and German tanks would have done even worse against T34s - altough it was not yet in service in 1939, but masses of Soviet light tanks would have been almost equal to German Panzer 2s and 3s.