Annapurna Trek 2018

In March 2018, I'm heading to the Annapurna region of Nepal to trek around the hills for five days.  Unfortunately, given that it takes around 10-14 days to do the full Annapurna circuit (plus two days to get to Kathmandu, and a further day to get to the start location), I won't be able to do that particular trek.  But there are plenty of others that take around five days, which is still going to mean a trip away from home for 10 days.

The plan at this point is to land at Kathmandu (found a flight with Turkish Airways from Birmingham for just £363 return!) and make my way to Pokhara.  There are various options for this journey, from the most basic, native-style, (taking 10+ hours), to a short flight (25 minutes).  What the latter option lacks is the opportunity to really mix with the locals.

Once in Pokhara, I need to arrange a guide.  I could theoretically trek alone (many do), but:
a) How would I know what I was actually looking at?  I could miss out on plenty of facts/history
b) It would be great to give something to the local community by hiring a guide
c) I'm sure I'll get to know these people a lot better as a result of chatting/hiking with a guide for five days than by being on my own

I've no idea how long arranging a guide will take, or how soon he will be ready to head off into the wilderness for five days - and it's this that makes the travel options to Pokhara questionable.  Should I just get there quickly and get the guide and our route arranged, or do I risk an adventurous journey at the potential cost of a day's trekking?

Having done a little research, potential routes include:
Everest View Trek
Langtang Trek
Poon Hill Trek (I'm currently leaning towards this one)
Mardi Himal Trek

If anyone has any suggestions/advice, please let me know.  I am limited to a five-six day trek, but I am planning on moving at a greater-than-average pace.

In physical preparation, I've started upping the distance I put in my legs each week.  I'll blog some of my treks and adventures between now and March 2018 - see the Trekking Masca blog I've already done as an example.