There is no difference between spider and ghost other than you have to wait 5 levels. Cost difference suggests to wait the 5 levels. So no contest beween Ghost & Spider. L35 Spider wins that battle hands down.
The L33 odyssey is a different proposition. It boasts 1 & 1/2 dots more than both the above. If you were to wait for a better putter than the odyssey then you would have to wait until L70 for its older brother to beat it. No other putter between L33 and L70 even comes close.
So if you get the L35 Spider, will you be happy with your puchase and not buy again until L70?
I think that if you do settle for the L35 Spider you will get itchy feet again in a few weeks time and you will be back looking for a better putter. Save yourself the grief.
If I were you I would get the L33 odyssey and not worry again about upgrading my putter for a very long time (at least L70 & above).
(By the way I never owned one, they were not around in my time but I am just doing the math for you :))