Anyway getting back to the question, if I were you, I would read up watch vids etc regarding dry barrel guns.
They might not suit your needs but that is what I use as my every day gun.
In my case I use a 90 cm Omer with a Tomba free spear kit fitted, I can only say what I feel from my own personal experience but that is a awesome set up with adjustable power, no recoil &.... lots of power.
One thing I enjoy about the gun is that you can see the spear in flight, not always of course but quite often once the spear is launched you can see it trajectory & that gives you such a great insight as to were to aim for the next shot.
I also fire a 6.5mm 100cm spear & that more often than not goes straight through the smallish fish we shoot.
If that happens then the fish cant struggle against the solid spear & rip off as it is just on the spear line.
Not everybody's cup of tea, however if you get a chance to fire one, I think you would be impressed, loading one at high power settings will be a leaning curve but you can up the air pressure as you get the technique down.
I am certainly not trying to convince you but perhaps worth studying dry barrel air guns a little more