How long are the legs?
Just some quick math...given a constant 200mph TAS, here are the g levels, bank, the corresponding turn radius & time to turn 120deg:
2.0g, 60deg, 1552ft, 11.1sec
2.4g, 65deg, 1254ft, 8.9sec
2.9g, 70deg, 979ft, 7.0sec
3.9g, 75deg, 721ft, 5.1sec
5.7g, 80deg, 475ft, 3.4sec
If it were me, I'd do some turns through 120deg of heading at 2, 3 & 4g & see how much speed you lose on each. At the end of those, fly exactly level & see how long it takes to accelerate back out to 200. From there, you'd have to do some more math to figure out what gets you to the next turnpoint the quickest.
As long as the legs are long, your turn radius won't matter as much as how long it takes from the start of your turn until you're back at full speed on the new course (they're really connected, but my point is don't pick based on turn radius alone). Without any flight test on it & just guessing based on my 6's performance, I'd say pull about 3g's & forget about it.
HOWEVER, turns are certainly an important part of the race. A second lost in a turn can be the difference between winning or losing. I was in an EZ race about 10 years ago where two of the racers finished within a plane length of each other after over 100nm of flying. I say go do some flight test & figure it out to the gnat's a$$.
Edit: slowing down to turn won't help.
More Edit: This is blasphemy, but an autopilot tracking a GPS great circle direct-to route can save a bunch of time. My A/P is good to hold me within 0.02nm of course (120ft). That's way better than I can hand fly it.