Global Scale Modeller

I have a few questions
in my stash i am building up i have a pak 40 i have been told the figures that come with the gun are poor quality can you get replacements
i am thinking of adding a Panzer Kampfwagen II and Hanomag Sd.kfz. 251/1which one would you recommend i get first ???

The older Tamiya figures are far from the best available. The very newest ones are quite good. While your kit has older figures, build them up and paint them anyways, you may end up like them and you'll get some experience with figures. If you're not happy with the end result then companies like Dragon, Mini-Art and Master Box all make good figures and should have something in the way of the Pak crew.
As to the kit choice, I would say the PzII, it's much easier to paint a fully enclosed vehicle, where as the half-track would take more planning in order to avoid issues with getting a good paint job on the interior. But, if you're adventurous, the half-track could have been used to tow the Pak 40, so you'd be well on the way to a diorama....

Like Mr Hutton said for sure, figure practice is always good. Hobby fan has a great AT crew for a pk 75 and for a 88, they also have a nashorn crew the cost is what gives my wallet a stroke.