Since no one has mentioned it, an i7-4720HQ, may be thermal throttling in a laptop, depending on the chassis and cooling design. While theoretically your laptop CPU may be more powerful than the latest i3 Skylake design, it might not turn out that way in real life, particularly in sustained load
If you can hang on until 200-series chipset is out (I think by years end?) it's supposed to be compatible with Cannonlake, which would give you a nice option to upgrade in the future without having to replace your motherboard. I would not expect Cannonlake to be backwards compatible with 100-series.