I would go for a 100g overfill. As mentioned by mountainm Shewie is selling a TQ with the overfill and its likely priced less then what will be in sale. Plus if you place order in UKH sale it will be probably the full 3 weeks before you get it because of order backlog.
With regards to your pad, have you tested this outdoors in your hammocks yet? I have tried a NeoAir inflating mat combined with a cheap down bag in my bottom layer of hammock and just couldn't keep my lower back/sides warm enough. That is why I have opted to go for a UQ.
I have used it with my DD, worked ok although the bottom of the hammock was dampish, not sure yet was it because waterproof nylon or the pad. No problem with cold shoulders as I'm a big bloke and I always buy the biggest pad available (my current one is 197cm x 65cm). Also I'm mostly a side sleeper and always wear at least a tshirt or something with long sleeves to bed. Keep in mind I haven't hammocked below +5C yet and when you are above +10C it is really hard to get cold, as long as you have some insulation above and underneath you your body will adjust/compensate.
I want to get my top quilt right as this will be my central item of insulation: top quilt for 3 seasons in the hammock and on the ground or in a tent with my girlfriend.
Bottom insulation for 3 seasons is a secondary concern for me as I'm quite ok with a shaped ccf pad (before), my exped self inflating pad (now) or recycled in to UQ sleeping bag (future).
If I decide to winter camp in my hammock I will use my top quilt with a peapod type contraption "Shug style" (Mat said he can make something like that).
I'm not yet ready for the UQ;
1. Can't give up the ground option the way I do outdoor at the moment (camp sites when going out with friends/girlfriend, or walk till I drop in Wales where treese are rather rare).
2. I got the tarpology all figured out from my ground dwelling time and last year with DD hammock. So now I will be learning diagonal lay, SRL, suspention etc on my new Woodsman X. UQ, peapods and winter hammocking I leave for the future as a next level.