Generally speaking all of these battles should show some sort of 'upgrade in strength' (or progress, rather) because after this they'll be up against the WG full frontal. With that in mind:
Nami vs. Kumadori:
Nami could use some mind games here. I think she could lie and say it is Kumadori's fault that the SH's got through to them, and cause Kumadori to blame himself. This could be a good distraction.
Nice idea. Kumadori's way of blaming himself for stuff is definately gonna be used.. but I think the main thing will be Nami finding out new uses for her clima tact and making her very strong because of it afterwards.
Sanji vs. Kalifa:
Obviously, Kalifa has a huge advantage over Sanji, even without the Devil Fruit. It's pretty obvious Sanji will be easily distracted by her, but he will find a reason to be angry at her (she insults his cooking, perhaps?).
Not too sure what to think of this one myself.. always found Sanji's weakness rather "lame" so can't comment much here
Zoro vs. Kaku:
This one's pretty unpredictable. Kaku already had the air-jumping thing going, and the DF brings an unknown into the equation. Really, there's no way to predict this without knowing Kaku's DF power.
The two serious types facing off.. this'll definately be the most serious battle of the bunch.. and probably end up in Zoro having to invent (or perfect) a new technique to beat Kaku, in reference to whatever Kaku's power turns out to be.. and then this 'upgrade' for Zoro will put him at a whole new level of strength.
Usopp vs. Jyabura:
This looks to be more of a stealth deal than anything. Pephaps Usopp's attempts to grab the key and sneak out without making a sound. Unless Jyabura's faking sleep, then Usopp's in for a battle. Rotten Egg Bombs may give Usopp a big advantage, as dogs have heightened sense of smell, which means an egg could affect Jyabura more.
This one'll be mostly comedy and talk and mind-games I reckon. I think Sogeking is finally gonna do Jyabura in by using every dirty trick in the book.. including using Jyabura's "mental weaknesses", ie his pride and all that.
Franky vs. Fukurou:
We don't realy know about Fukurou's abilities at this point, so this is another one that's tough to predict. I'm guessing this'll be the most comical battle of the bunch.
Another one that'll have some more comedy.. Fukurou definately showed a more serious side in the last chapter, but still.. he has a zipper mouth.. and his opponent Franky is also a rather wacky character so this fight is likely a disaster waiting to happen. Probably will boil down to Franky showing off some new moves to best Fukurou, to show that he can keep up with the advance of the strawhats and is indeed a good candidate to be the newest crewmember.
Luffy vs. Lucci:
Luffy'll be at near death, proclaim something, then whip Lucci's ass. Like all his battles. Or at least what I've been getting from them.
Yeah this is a no-brainer ^^ Lucchi will be totally cocky throughout the entire battle, giving Luffy heaps of trouble almost effortlessly.. taunting him along the way.. and Luffy has to cling to straws to keep up.. and when he's almost done for, something that's been said by Lucchi incites Luffy to make a stand in his resolve, and subsequently he'll nail Lucchi in a final attack.
Something tells me Chopper's gonna end up facing Spandam and Funkfreed. Tough battle with Funkfreed, perhaps, but I'd think Spandam would be relativley easy to defeat.
I can see this happening too.. and that the battle will be more Chopper (zoan) vs Funkfried (zoan) than vs Spandam. As I said in another thread, I think Spandam is more of a goof but that the sword itself is the real fighter in this duo. So like the others, Chopper will have to face some demons of his own before finally being able to best the sword.
EDIT: Hm, turned out more elaborate than I expected. Gonna save this for refertence and see how well I can predict Oda after the fights are done ^^