Enstrom is usually flown from the left, however it can legitimately be flown solo from the right - exept there is no starter button on the right. I have done both and it makes absolutely no detectable difference to the way it flies, apart from it flies right skid low when P1 on the right. The mast on an Enstrom leans to the left which apparently counters the C of G thing to make it hover level when lard arse is on the left. It seem to work.
As has been said before, no centre lever with 2 pax so P1 must be on left. A bit of a no brainer really.
Someone said about hovering an R22 whilst fiddling with the radio. I vividly remember my instructor demonstrating what happens when the pax leans on the lever to get comfortable whilst doing this. Believe me, its safer to land first!