MBP 2015 thunderbolt 2/3 new MBP ?

I'm a bit on crossroads.... I have a MacBook Pro, early 2015 13" 8GB RAM 256GB SSD, and an Intensity Shuttle Thunderbolt 2, I really want some fast external storage space to swap, to directly capture video onto, and also fast access for audio files used by a Pioneer DJ controller.
Most fast external SSD's use USB-C my MBP has USB 3 .... Other/most superfast SSD's use Thunderbolt 3..
Can i use a ThunderBolt 3 on my MBP which has Thunderbolt 2 ? (only interface/speed bottleneck?)
What if i buy a new generation MBP (with Thunderbolt 3), can i still connect my Intensity Shuttle (ThunderBolt 2) directly to that new MBP ?
It comes down to that i want fast storage speed, how to do this, and keep using my Intensity Shuttle (TB2)...
Interfacing is the main problem i guess....

You got me curious. I am always looking for more speed. I was going to say that you would be hard pressed to get drives that fill a USB-C pipeline since it can handle 10Gbps (1.2GB/s) and an SSD tops out at 550MB/s. But there are M.2 drives that can do 1.8GB/s.

I saw an interesting array from OWC that houses four M.2s. In theory that would top out at 7.2GB/s (57Gbps) but the OWC site claims 2.8GB/s (22Gbps) - just slightly over a TB2 data rate of 20Gbps (2.5GB/s).

You can connect Thunderbolt 3 devices to TB2 (generally). Per OWC: 'Moreover, the OWC Express 4M2 is backward compatible with Thunderbolt and Thunderbolt 2.'

Thunderbolt 2 devices can definitely be connected to TB3 hosts. I don't see any reason why the Shuttle would not work on a newer laptop with the Apple TB2<->TB3 connector. If you are thinking of buying a new Mac, take the shuttle with you to the store and ask to plug it in.

Do you have more than one thunderbolt 2 controller in your laptop? (Probably not since it is a 13".) Would there be enough bandwidth in the TB2 controller to handle the shuttle and a fast SSD? Between that and the fact that you only have 8G of ram, I would lean towards an upgrade. The 15" (if I understand things correctly) have 2 Thunderbolt 3 controllers (each with two ports) so you get maximum speed by using one from either side of the computer. Then you could use an M.2 array and the Shuttle without filling the pipe. You could then also add an eGPU for even greater performance.

You have started me thinking about upgrading my SSD array (top data rate of 1.2GB/s) to an M.2 array (claimed rate of 2.8GB/s).

Thank you, for your answer ! I conclude from it i should really upgrade to an iMac Pro, when you're talking about SSD arrays yes, more system RAM would also be good upgrade anyway,
My MBP does have two TB2 ports, also a USB 3 controller, two USB ports, don't know for sure if both are 3.0.
So, i'm very tempted to buy a good Mac , No Microsoft Windows PC for me anymore, I've had a lot of touble with that, I'm very happy with the Mac OS, it's safety, and stability.
I've also a Lumix G7 so easy workflow for 4K would also be nice, also recently bought the Insta360 One X....
Most of my Internet devices i have hooked up through a Gigabit switch, also thinking of having a NAS again for storage, my last one (Qnap) crashed, on one hand i liked the OS of it but on the other hand it did not repair damaged sectors, which was the reason for the crash is my guess.