Hm. I understand your goal here, but I think you're going to be spoiling a lot for yourself if you read anything in the A Time To... series or later before you watch the DS9 and Voyager TV shows. In particular, the ending of Voyager is crucial in the setup for much of the TNG stories post-Nemesis, including Destiny.
Also, I don't know if you've seen the flowchart linked in my signature, but it's super helpful for lit continuity in general.
A few quick notes, then broader recommendations:
- The Vulcan's... novels aren't essential and could be skipped.
- Star Trek Online isn't in continuity with the LitVerse, and there's only one novel related to it, which nonetheless does spoil/reference some elements of the LitVerse. You probably want to skip that completely.
- Vanguard is fantastic, and more important than you'd think. Read it before you read anything titled "Typhon Pact". I list it below right before Typhon Pact, but if you want to get a taste of how awesome the LitVerse can be early on, these are also fantastic reads just after you've finished TOS.
- Lost Era has some connections to the DS9 Relaunch and to Titan. See the flowchart in my signature for details.
- Never Ending Sacrifice is fantastic. It's skippable, but don't.
- Any Enterprise novel that's not part of the relaunch (ie, any ENT novel before "The Good That Men Do") is likely pretty terrible and also totally irrelevant. Skip those.
- EDIT: one more. The Left Hand Of Destiny isn't important at *all* to the rest of the DS9 relaunch, and you probably only want to read it if you plan on reading the Klingon Empire books, which you can also see detailed in the flowchart. Those books are referenced a few times, but they're more in the category of New Frontier or Stargazer, and aren't essential.
So, I think what you want to do is this:
1. TOS - selected episodes
2. TAS - selected episodes
3. TOS films
4. TNG - selected episodes
5. Generations, First Contact, Insurrection
6. DS9 - selected episodes
- Hollow Men novel - after 6x19
- The Battle of Betazed novel - before Season 7
7. Selected Lost Era novels (see flowchart), including Terok Nor trilogy
8. DS9 relaunch novels starting with The Lives Of Dax and A Stitch In Time up until and including The Never Ending Sacrifice (also with the Mirror Universe novels, probably - see flowchart)
9. VOY - selected episodes
- String Theory - between Seasons 4 and 5
10. VOY relaunch novels up until and including Enemy of My Enemy
11. ENT + ENT novels + ENT relaunch novels (in internal-chronological order)
12. A Time To... series
14. Post-Nemesis novels up until and including Destiny (TNG, Titan and Articles of the Federation) and everything between Destiny and the Typhon Pact novels
15. Vanguard (here or at any point previously)
16. Typhon Pact novels and everything that follows them