Hi, I just picked a medium Western Mountaineering Flash Jacket to use over my base layer and under a shell. It is an awesome jacket in terms of warmth and weight but I am concerned about the sizing.

-The sleeves seem a bit short as they stop just before the hand.
Is this to allow room for gloves?
What is the ideal end point for sleeves when the arms in a relaxed position at one's side?
How much extra length, if any, is needed for them to ride up when moving them?

The jacket has an elastic band at the bottom that keeps it pretty snug to my body. However, it always ends up exactly right above my pants.
-Once there it stays in place, but is it supposed to cover any part of the pant, or is that the job of the outer shell (and the pants of course)?

Would appreciate any advice anyone has...my other choice was the less warm RAB microlight jacket...but the guy at the store said it was too boxy for my frame (broad shoulders relative to waist) where as the Western Mountaineering was more tapered.

Thanks!

-Omer

I am new to the gear world so I might just have to accept that there is no perfect fit!

Only you can decide it the fit is adequate. It sounds OK from your description. If you like it AND the price was a great deal then wrist coverage will have to come from your base layer long john shirt.

Sew a thumb loop of elastic on the thumb side of each sleeve cuff to hold the base layer shirt sleeve down and over your wrist. Many base layer shirts already come with thumb loops.

I have one of these in medium as well. It fits me about the same as it does you. This is fine for me because if it is could enough that my wrists not being completely covered is a problem that I will probably be wearing a long sleeve base layer and gloves anyway. Once you get into really cold temps 10 and below, then having a parka that fits correctly is much more important.

The sleeves are short and the length is short - sounds like the jacket is too small on you. Go a size larger.

I think the points you listed are really personal preference, and whether they bother you enough that you would want to look at a different jacket. I had previously purchased the WM flash jacket (Wm S, 8.92 oz wt), but returned it for a MB Alpine Light Parka (M's S, 14 oz even)- it fit much better than the women's version for me- longer, more fitted torso and sleeves) for a few of the reasons you stated. Those points bothered me enough that I was okay with a 5 oz weight gain. ymmv.

-The sleeves seem a bit short as they stop just before the hand.
Is this to allow room for gloves?
What is the ideal end point for sleeves when the arms in a relaxed position at one's side?
How much extra length, if any, is needed for them to ride up when moving them?

I think that this is a very subjective thing. I like to have the sleeves long enough to just hide my hands in if need be when it gets colder.The WM sleeves were not long enough for me to do this- M's small or W's medium.

The jacket has an elastic band at the bottom that keeps it pretty snug to my body. However, it always ends up exactly right above my pants.
-Once there it stays in place, but is it supposed to cover any part of the pant, or is that the job of the outer shell (and the pants of course)?

The elastic band fit snug on me as well, but would ride up a bit when i sat down or moved. The MB Alpine light has a draw cord so I could cinch it a little looser so that it wouldn't do that, but still provide a close fit. It helped that the torso length was a bit longer as well for me.