I think as long as the map is playable online without lag, whichever map size you can get for that purpose is the best.
With good publicity, you can have people download the map online prior to playing, eliminating the need to download large maps. I personally play large maps, and know this would bring in more players.
A friend of mine also used programs to reduce the map size, so if you search enough i'm sure you will find a solution.
Also try and remove any extras that are not necessary, like animations for doodads, etc. Say if it is a tree, animation is not necessary, so you could free up space by just cutting back a bit.
Yes but loading time is also a concern for me. Its very frustrating waiting for a 12-person game and then having to wait 10 minutes for the game to start because one players internet sucks.
I have searched long and hard for any and all methods to lower map size and I've used most of the ones I could do/understand/get to work. I haven't been able to get BLPaletter to work, I don't know if there's a better way to compress BLPs outside of lowering the quality, scaling down the file size (both of which I've done). I don't understand how to reduce a BLPs color count or when and if I should.
I've been using MDLVIS and I removed all the animations that I didn't think I would need, then optimized and squished.
I've also used BLP lab on top of lowering the quality of every BLP.
I know about Optimizer and Widgetizer, but like I said I don't think Optimizer will be enough based off comments and Widgetizer broke my map last time I tried getting it to work.
Edit: Is there a way to further reduce MDX sizes and BLP sizes, aside from MDX Squisher, MDLVIS Optimizer, removing animations, lowering the quality of BLPs, scaling down BLPs and aside from using BLP Lab's Optimizer?
I just discovered this after a more thorough search of the website,
http://www.wc3c.net/showthread.php?t=101586 but I'm a little worried to use it, it sounds too much like the Widgetizer and it doesn't look like its being supported anymore. Has anyone used it before?
Thank you for your help !

+rep