Clothing
You will obviously need clothing suitable for the time of year you choose. When we went (April) it did not rain much, but it did get a little cool at night. During the day it was sunny and quite warm; some days were even hot.
I carried mostly Icebreaker wool layers, one synthetic T-shirt, soft shell pants and a Goretex shell jacket. A brimmed cap or hat for the sun is very useful as well as a warmer beanie for nighttime. I always have my ultra light down jacket with hood, which is also used as my pillow.
Light footwear such as trail runners is quite sufficient. Several changes of socks. Possibly flip flops for non-hiking periods. However I didn't take them nor did I use my gloves.
Sleeping stuff
Highly recommended. Sleeping bag (and if you have one a liner sheet), mattress (I use a Thermarest 3/4 length ultralite). Optionally consider a tent if its benefits to you are sufficient. I always have my piece of yellow closed-cell foam as a sitting pad.
Water purification
We carried Micropur tablets. The main benefit being they weigh nothing and work. We also had a Steripen. It is Magic! Drinkable water is ready instantly. This is very useful when water sources are some distance apart and you need to drink immediately, top up again and leave. Take spare batteries or consider the USB rechargeable model.
Cooking gear
I carried my gas stove (MSR Superfly) and a couple of canisters (buy these in Pokhara as there are none available en route). Plus a titanium cup, titanium spoon and an Opinel knife. I also have a piece of heavy duty aluminium foil as a windbreak.
Being able to boil water was very handy, though limited to making tea/hot chocolate and (noodle) soup.
Other
• The usual First Aid kit and hygiene stuff.
• Something to read apart from the map. I carry a Kindle.
• Camera, spare batteries, SD cards
• Headlamp
• Swimming trunks and trek towel for the occasional bathe.
• Passport
Power
There was at least one option to recharge electronics but with a battery pack I didn't really need it.
Cash
There is no alternative and best to have a stash of small bills. And hang on to change whenever possible, as it can be difficult to split even a 100 Rupee note. A budget of 1000 NRs a day was never exceeded and indeed the average was closer to 4-500 a day ($4-5).