ISight is the best for addressing accuracy and effort. The accuracy is shown in Axels paper and it is pretty easy to use. IMHO it's killer feature: it gives a winning percentage so it is usable in matches as well!
Isight has one shortcoming: for longer races an even race is lower than 50%.
According to ISight add 1 for the 3rd checker on 2, 1 for the hole on 4 and 4 for additional crossovers. So addjusted pipcount is 100 vs 111 giving 80-(100/3) + 2 * 11 = 68.67. Too low. See here in Colour: 
if you replace 80-(100/3) with 58 which is reasonable you reach 80%. A further slight flaw I see is that holes count even if there are a lot checkers outside that could fill the hole. If you adapt this as well you reach 78% which seems pretty good.
BTW I see another slight improvement in Isight and I hope that Axel considers them somehow. If not I'll publish my suggestions in Spring (and the support as above in BGBlitz exists already....) It improves Isight by about 8% and it is still easy to use for humans