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@Glowbike
Hi Constant,
This is a bitof a brainfart but I hope it helps
I was running a 69mm trail on a longer wheelbase jumpbike (420mm CS, 590mm F-c) and it felt nice cornering but the steering was heavy. I didn't want to add any more trail as I didn't want to make it feel any heavier.
When I had my own frame built I lifted the front end geometry (69mm trail and 74 deg headangle) and shortened the rest of the frame a lot.
With all the extra weight on the rear wheel of the new bike the front end would feel very light, understeer and be more prone to jack-knifing early.
I was running an adjustable length fork for messing with headangle and trail, so I spaced it from 74deg out to 73deg w/ 20mm Rake on a 642mm OD wheel. This has added a bunch of trail and the bike rode so much better for it.
I then got a Maxpower fork with it's 10mm rake so I can mimic the same trail with the steeper 74deg headangle.
I suggest those bikes above will have light steering and jack-knife early due to not enough trail.
A simplistic explanation for polo frames:
The headangle dictates how well the bike will ride at low speed. (it changes the speed of steering inversion)
The trail dictates at what point the bike will jack-knife.
If you're small then get your fit correct and your trail to a reasonable number and let the headangle be where it needs to be. Loss of low speed stability can be corrected by rider skill but a badly fitting frame cannot.
Also those frames both have quite long front-centres. I can run 560mm F-c with 170mm cranks and 642mm OD tyres. I have overlap if I point my toe, but when I'm riding hard I drop my heels anyway so it's never caused a problem.
One more thing, if you're ordering from Marino try to have some reasonable tolerances to all your clearances as it probably won't turn up quite as ordered.