Honestly speaking, there's no answer to which one is best. It depends on what you prefer. And if all the speakers are available, what's even better is that you demo them. My opinion will differ from the next guy and I'm sure this is going to be the start of a yay or nay discussion but this is what I think
I've never been a fan of 718s. Kenwood has much better speakers now a days especially their excellon series. But I think they're way too boomy and the tweeter isn't balanced at all
The 6975v2 were great speakers. Old but good. But again, I always found my 6992s to sound better. I think probably because people compared the 6975v2 to the 718s and pioneer fan boys used to open the gain until clipping just to match the 718s for BASSSSSSSS.
I've not tried the type S 6x9s but I did run the coaxials back in the day and I loved those. I also was using the jbl gt5 comps and compared to those, these sounded more balanced and mellow. What we call warmer sound. But what lacked was the midbass, which by no means was bad. But this was also back when there was not proper sound treatment done to the doors and panels to give the correct platform for those midbass drivers to perform. I'm sure the midbass will be much better on the 6x9s
So from the lot here, I'd get the alpines for a more balanced sound. Pioneers are always great if you are looking for something dynamic. Not too harsh and the midbass is always there. I'd also look into kenwoods but definitely not the 718s. Just not my cup of tea
But again, it depends on you, the prices you're getting these, what you're powering these up with etc etc