advice sought for building up a 10

hello all,
i'm assemblying a 10" f/6 newt with a conical primary from bob royce. the scope will do double duty as my deep sky and planetary scope. i have some ideas on setting it up and i'd welcome input/advice. i'm not interested in spending tons of money on this, but i'll go a little extra if the payoff is a discernably better view on those rare nights of magical seeing here in southern vermont. here goes:

a 1.83" secondary looked like a nice compromise for my purposes.

i'm thinking of using the protostar curved spider.

protostar offers building in the secondary offset on the holder. while it is not a large offset on this scope, it seems like a good idea.

how flat is flat enough on the secondary.there is quite a range of specs out there. any prefered suppliers out there?

i might try a kineoptics 2" focuser.

construction will probably be sonotube (perhaps split tube) on alt az mount.i'm fairly settled on this and can live with the drawbacks.
thanks,
glenn

Glenn,
I just got a curved vane from protostar for a 2.14" secondary at 14" diameter cage. Fabrication looks excellent and the spider seems realy stout. I also got my secondary from antares optics. I asked if they where having a sale and they came down about $30 on a 1/20 pv wave.
Good luck!
Todd

Glenn,
A good secondary is worth the money because all the light from that bigger mirror has to be reflected off the smaller one. The less the secondary effects this light the better the resolution and contrast. You can do 1/12/ to 1/15 wave and do fine, but a 1/20 would be nice if you can afford it.
Remember one thing, if you are using a minimal sized secondary, then you need the better wave rating, because you will be using the mirror to the edge where most of the problems on a flat occur.
Floyd