DNA250 build with flashlight and wiring questions

[Critter Mods]

Hi guys, I'm returning to modding since my last builds with dna25's and excited to try some things out.  My design will have 2 2x700s powering a dna250 board, and I have seen some conflicting answers here and elsewhere about wiring so I thought I'd come out and ask.  FYI I vape (don't laugh) 0.1 ohm Revvo coils at 45-50W but occasionally bring out a squonker or an RTA from time to time, never above 70W.  

Q1) Some people have said to wire in series, and I've seen T1—T4 bridged with B+, and it's getting lost in the way my head organizes things.  Here's my plan, please tell me if I'm wrong:  I'll bus the B- with the two negative ends of each battery.  In fact my design has a copper "endoskeleton" so I'll use that for bridging/busing, solder to B-, and as Gnd for the 510 **[subquestion: can I still use that for up, down, fire switch negatives?]**  Then, can I wire cell 1 + and cell 2 + to the board in the "1" and "2" holes in the first image?  I don't see a reason to use the 4 pin connector, electrically it should be equivalent, right?  I'll throw a pig tail into the GND hole from my B-/Gnd endoskeleton just to be thorough as well.  This doesn't seem like series or parallel, but individual--do I need to bridge positives for any reason?  Seems like you'd lose the individual cell monitoring and charging.  

Q2) If each cell's positive is separate, then what is B+ on the backside of the board for?  If you were to use their suggested 3 cell Lipo with the connector, what, if anything, does the B+ become? Or is it just there in case you want to run a parallel/single cell?  

Q3) If I were to run an LED for a flashlight, is there a "combined" positive to tap into?  I could tap off of just one cell, it won't draw much or be used much, but without busing the positives anywhere (if what I said in Q1 is true) I don't see how to draw this evenly off the batteries.  I don't like the idea of creating imbalance in the mod, but if it must be done....  Just to clarify, this would be for a flashlight, not connected to the fire switch. 

Here's my old dna25 builds from a while ago, looking forward to getting back into it and thank you guys for any help you can give!!