There’s alot of stuff to unpack here. So let me dive in.
I currently have a Tsunami 175 - so similarly classed boat as your Tempest 170 though your tempest has a slightly narrower beam but for all intents and purposes they’re close enough to be the same.
I’ve also paddled a Field and stream 14ft a Fusion 124 (12ft.) a 10 foot Aspire and a 10.5 ft one too and a 2022 Tsunami 145 (my Sons.)
with exactly the same paddle the smaller boats will accelerate faster, however they also hit their top end quicker. The longer boat will take a little longer to hit it’s top end but will have a higher one as well as carrying that speed longer between strokes.
now I’m not going to go into swing weight vs. fatigue vs top speed over time so the numbers I’m going to give you are all within my endurance of each paddle in the Tsunami 175
so having said that I had a Accent Paddle, with a fairly large blade area, 652cm2 pulling on that paddle I could hit and maintain somewhere in the 5.5 to 5.9 mph. and during one race when I was the leader I was clocked at 6mph. but that was only over a course of about 7 miles (thats my fatigue point for that paddle.)
The cadence here was moderate for me using that paddle. about 30SPM (Strokes per minute.,)
for the next race I was in I used a aqua-bound whiskey which has a blade surface area of 613cm2 Over 3 miles my speed was 5.90 mph Time clocked, but because of the smaller blade area my i was averaging about 45SPM to hit the same speeds.
However I found that I was spent after 3 miles.
Apparently I’m better with slow twitch muscle fibers than fast twitch. (we can get into this later.)
So finally I opted for a Werner Ikleos paddle this comes in at a whopping 691cm2 and i find that my cadence with it is much slower generally between 24 and 28SPM. Hitting the same 5,5 to 5.9 mph. (GPS measured.) however this was only over a shakedown run of about 3 miles and I had not hit my fatigue point. with it in that duration.
all the paddles were 220cm long except the Ikleos which was a 225 as a compromise. I have the other two paddles in both lengths of 220 and 230 each. and will choose the paddle length based on water conditions on race day and take the other as a backup
also all the paddles were within 2oz of each other (actually the aqua-bound nd the accent are the same weight and the ikleos is 2 oz lighter.)
I did do a relaxed run with my Tsunami and the Ikleos holding 4.85 mph which I felt I could do all day.
So it comes down to this for me I am a high angle paddler, which is a more powerful stroke than low angle. however my muscle make up is biased towards slow twitch so a slower stroke for me with larger surface area is the right thing, providing I don’t go too big and hit the point where I have more paddle than I can pull. I have found in approaching this in a more scientific manner that with a faster stroke I fatigue quicker than I do with a slower one all thing being equal and normalizing for speed.
Now this is right for me but depending on size strength muscle type (are you a sprinter - fast twitch or a marathoner - slow Twitch.) it may not be right for you.
If high cadence is the thing you do then a smaller blade surface is probably a good call. Most rental places should have Werners which will have a smaller surface area, try them and see.
then look into swing weight, the aquabound and the Accent are the same weight but the accent is more blade weight biased where the aquabound is more shaft weight biased. so it takes more effort on the Accent to paddle but because of the larger surface area and lower strokes per minute it takes longer to fatigue me at the same speed.
No I don’t have long haul data yet on the Ikleos (having gotten it last year at end of season.) but hopefully I can update when I have times for the yet to be announced 15 mile run I enter in yearly.