In a recent post, you wrote "Eske ou ka ban mwen'l a yon pi ba pri." The use of "a" to me in this seems a bit Frenchy? Can you state some other constructions that use "a" in this way?

Yes, your observations are right.
You're talking about the French preposition "à".

You'll also see this preposition "a" when Creole speakers indicate time:
Nou vini a midi.
We came at noon.

Yo te rive a lè. (also 'alè' from French 'à l'heure')
They arrived on time.

N'ap koumanse a sizè.
We'll start at six o'clock.

Creole speakers might use it when talking about distances.
Pye bwa a te a yon distans twa pye konsa.
The tree was at about a three-feet distance.

Also when talking about manner or mode
Machin nan t'ap kouri a tout vitès. (from French à toute vitesse)
The car was going at great speed.

Others instances that you'll find may be written as one word in Creole.
alamen (from French à la main) → by hand; 
Yo te koud li alamen.
It was sewn by hand.

apye (from French à pied) → on foot;
Mwen t'ale travay apye paske machin mwen anpàn.
I walked to work because my car is broken down.

afòs (from french à force de) → by dint of
Afòs mwen te mache pye'm fè'm mal.
I walked so much my feet hurt

akoz (from French à cause de) → because of
Reyinyon an ap fèt anndan akoz lapli a.
The meeting will go on indoors because of the rain.

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