I'm considering attending qepHom X.
I didn't attend the last couple of qepHommey, and didn't completely enjoy the last one or two I did attend (mostly because they didn't live up to the first one I had attended in terms of how much time was dedicated to learning and using Klingon; my last one had chunks of unstructured time, which I found hard to make good use of).
But this one is a nice round number, plus Marc Okrand and Agnieszka Solska have already indicated they will be there. In fact, quite a few people have already signed up; 18 as of this writing, and that's not even counting those two, as far as I can see.
When I mentioned this to Stella, she seemed to have given her OK, so I can make more definite plans.
Now the two main points to figure out are when to arrive, and how to get there.
The main conference will start on Thursday "after lunch", but the page explicitly says that those who arrive on the previous day will be able to use the lobby for studying (and, presumably, talking) - and when signing up, you have the option of specifying arriving on Wednesday. So that's attractive. And also because getting there by train takes about seven hours; up to nine on some connections. So I'd have to get up pretty early to get there by noon on Thursday.
This is also a consideration for leaving on Sunday. The conference as such will finish sometime after lunch; the page leaves it a bit vague and says that the end is "in the afternoon". So having to leave very early in order to get home the same day would also be a bit annoying.
An option would be to take an overnight train; but on the way there, I'd have to get off the train at 5:20 in the morning, and on the way back, I'd have to get on at 00:58. Both of those times are not all that fun. (Though in fairness, the train's times are geared towards Paris, not Saarbrücken.)
What I might try is going first class: if I book far enough in advance, I might be able to get there for under €100 return, which is even cheaper than a 50% reduced full-price ticket (at €125), and might be more comfortable on such a long trip.
Then there's the option of flying: a lot quicker for the raw travel (1:15 instead of 7:30), but then you have to add in the times travelling to and from the airport, plus time from checking in to boarding and the time for retrieving your luggage, which makes flying less competitive at shorter distances but probably still gives it an edge for this distance.
Right now, I can get a flight at pretty good times (9:00-10:15 Thursday, back on Sunday at 18:45-20:00) for €118, which is excellent.
But then you have to get to the youth hostel. The bus connections on Thursday aren't that bad, except that you have to either cut the connection fairly fine at the main station or walk several minutes with a big suitcase, but on Sunday, the bus doesn't go terribly often, so a taxi starts looking like a good option (especially with the suitcase), but that adds to the price again.
Plus you have the usual problems associated with flying: luggage limits and asinine security restrictions such as how much liquid you can take, and would you prefer the enhanced patdown or the naked scanner?
So, I don't know. Tentatively leaning towards taking an early train on Thursday (and getting there around 13:24, which is perhaps a bit late for "lunch", though) and then going back at 16:47 or something like that. The availability of discount first class seats may well influence my choice of trains, but I won't be able to see that until 90 days beforehand, so 15 August.