Hey dude tht tech tree is do-able.. wat is it u dont find possible???
I mean iv seen whole battle cruisers being made iv seen MAC cannon rounds..
v not make ODST drop pods they will look like tiny projectiles falling to the ground..
and small slow dorships is no problem.. Depending on how long the capital ship was bombarding the planet the number of troops sent which increases the speed of the decrease in population so if the capital ship leaves the troops stop comeing but if the planet population is low enough the planet still gets captured aftr some more time(coz of the remainin troops on the ground)
kind of the same thing applies to Ship boarding..
and dont tell me its to difficult to put an EMP blast on a Nuke coz there is an EMP blast feature on one of the TEC cptl ships.. so its kind of mingling a nuke an it together

... mines can just b stagnant nukes suspended in space like an invisible structure..
stealth cruiser idea i dont think will b tht difficult if u ask around iv seen it in mods for othr games where characters get an invisiblity option on them...
i know im pushing my luck with all these idea's but im a die hard halo fan and im amoung those ppl dejected by Bunji's Xbox360 only policy
anyway good luck on it....
im sure u can do it if u put a lil thought in it.... v r routing for u to make it gr8!!!!!!!!!!!!!!!