We already have the chameleon spy (completely different, but he will regain some of his TS abilities via the Sabotage beacon), however the stuff you posted would not fit. We discussed potentially merging the upgrade center and the radar, but decided against it since some mappers would want an upgrade center but NOT a radar. The threat rating node would be absolutely useless in TSR as well. The only way I can think to implement it is when it dies, it replaces the base defence scripts with the old "dumb" scripts, but this would leave GDI at a disadvantage compared to Nod.
The Kodiak and Montauk may appear in some maps.
Not stated yet.
Yes.