Shut it, post-finale spam is traditional
1. I have spidey-sense of Martha not returning full-time. I think she's going to get to be something New Who quite needs format-wise, which is a home base. She'll hook up with Whathisname and that + Lonely God makes me wonder if she's going to be the Doctor's substitute family now. Which'd be good for Ten because it means he has friends who aren't dependant on his current lover companion sticking around, and Martha can't really go back in the TARDIS for good without needing to undo a lot of her awesome. As with S2 Rose and who wants that? Like I babbled in comments somewhere, once the companion's saved the Doctor + World there isn't much left for her to do that's still progressive to her character. After that you're into playing with flaws and making her lose her powers so that plot can happen. (Post-S1 Rose still gets repeatedly locked in rooms and captured. I try not to think of the girl as stupid, but plots needing her put in danger don't help by being lazy.)
They can't use UNIT (apparently) and Torchwood is off-limits in case The Kids want to watch the pr0norama that is Team Cardiff. This leaves Martha. Martha who is a doctor (and let me put in a tiny bet here that when Ten eventually dies he makes sure Replacement takes him to Martha for the regeneration). Martha who can give helpful advice to her successor and give us many comedy scenes of the Doctor being a bit domestic every now and then. What she replaces is Gallifrey, only not because that'd be sick. And what's the betting that Ten is Comedically Jealous of the fact that his woman has a new man? Just cos he doesn't want her doesn't mean someone else gets to have her!
2. I don't like the precedent of alternate companions being used to rebound from the previous one. With 13 eps a season it wastes time the series can't afford and it's a cheat to the viewer. Most importantly, it's backwards-looking and I thought Rusty hated that shit. He's damn good at backreferencing for the most part, where he phrases stuff like legend so if you know it you smile and if you don't it's no loss. (Cos, really, how many people who watched that know what an Axon is?) Fandom can cling to backreferencing all we want (Yay Ten/Jamie OTP!) but bear in mind that mentioning Rose all the time was probably needed so that the viewer would remember someone who left a year ago. Even then it has to do it more on Martha Being Sad than anything else because otherwise there's no emotional connection.
Essentially I hope Replacement isn't subject to Ten's whiny emo about the fact that Martha left him. If only because Martha leaving him should have given him a bit of a hint as to why she left him and he'll have learned not to live in the past at the expense of the present.
Which assumes that Ten ever learns anything.
3. Note that the Doctor's plan is to send someone he doesn't love off to make everyone love him. So Martha really is Ace in that the Doctor uses her emotional suffering to defeat his enemies. That's harsh. I really like that because I'm sick. Thus the incredibly fucked up thing where Rose wouldn't have left him (she wouldn't) and Donna wouldn't have told everyone to love the Doctor. ("There's this bloke I know. He's a complete wanker. He wants you all to think about him. I wouldn't, if I were you. Next time I see him I'm going to cut his balls off. A year I've been walking the Earth in this wedding dress. All because his ex-boyfriend has some big floaty marbles. Martian bastard.")
4. Torchwood's finale was also shite. Both of them partly because the stakes were too high. Thing is, as soon as there's Torchwood and Sarah Jane's Lesbian Adventures that's it pretty much concrete that nothing major will ever change in the DWverse again. Moffat's the one everyone loves for plot, and you'll notice that he keeps it small. There's always the risk of something terrible happening, but the number of people in danger is relatively low. (GitF - traditional companion endangerment notwithstanding - has only one person in mortal danger.) And DW is an ongoing series that The Kids watch, so there's no chance of massive death (and I like that). So as soon as the bodies start dropping you know you're in for a reset.
And yet Rusty can't resist making everything Very Huge. So he starts killing people off all over the place and you know it's not going to stick. Rusty's other issue here is that he doesn't really do plot. Plot's just what happens to make the point ("the Doctor is Jesus and Martha is his apostle") so you end plot's by pressing a button. Sadly the button solution isn't really satisfying for the audience because that physical act is far too easy and the costs are low. (Though let us ponder here that Rusty has now twice punished the Doctor by taking his companion from him. There's a thing in there about characters with nothing to lose and how hard it is to make people worry about them.)
What I'm sayin' is, Rusty's addicted to big epic battles only he doesn't really like big epic battles so they just sort of happen in the background and then he undoes it all with a solution that's separate from the Big Epic Battle. RTD's Time War may be a mystery, but isn't it so fitting that the Doctor solved it by pressing a button?
5. I wish to see if S4!Ten is in any way upset about the Other Last of the Time Lords dying in his arms slashily. Since he ended the episode not that fussed we are perhaps to assume that burning the body served as catharsis of some sort. Though that seems wrong because it'd mean companions didn't fix it and Rusty likes to be able to at least pretend that they did. Not that I can be arsed with an entire season of "my evil ex-boyfriend is dead and my girlfriend left me because I wouldn't shag her" but if we have to be backwards-looking it could at least aim for consistency.
6. It would be nice if Ten has learned "No, people don't leave you by mere passage of time and circumstance. Sometimes they do it because you're a wanker." Because he'd be interesting to see without that sympathy card to play. Compare and contrast "my girlfriend is in another universe, it's not my fault" with "my girlfriend is... err.. she's at home and she left me because I treated her bad. I WON'T DO THAT TO YOU, HONEST. *sigh* I wish Martha was here. ARG STOP HITTING ME."
7. Jack can't die. Good, that's stopped me worrying about Torchwood's leading man. I'd hate to have had to get through a season of situations where he might plausibly get killed.
8. I like to think the Master regenerated into a woman. You know why? TIME BABIES! EVIL TIME BABIES! "My evil plan is... to shag you!" "That's always your evil plan." "...STFU, BITCH."
9. Maybe Owen was evil because of the drums in the mobile phone signal?
10. Martha/Toshiko. Shut up, it could happen.
It is can be Torchwoods tiem nao pls?