Here's why I don't like Smashville as a starter
1. If we don't count Bowser's Castle or Yoshi's Island(which many don't), then Battlefield and Smashville are the only 2 viable medium stages. If we're looking to balance the neutrals(which I am), then there's no way to do it with 2 mediums, one of them has to go. And between the two, I believe Battlefield to be a superior neutral, especially considering...
2. Smashville is too similar to GHZ in the sense of "smaller FD with a moving platform" and is ALSO very similar to PS2 in the sense of "Dash dancing and aerial wobbling heaven" GHZ and PS2 are definitely varied enough on their own, but Smashville bridges this gap between them that homogenizes the neutrals in favor of open space. You could argue that GHZ is the one to be replaced (as some scenes have already done) but then you still have 2 mediums and an imbalance in the starters.
Now if Bowser's Castle is still on the table, I'm all for Smashville as a starter cause 1/3/1 is amazing, but it's clear that Bowser's Castle has problems that may not be possible to overlook, so I'm considering alternatives.
Here's what I like about this proposed list of starters
1. 2/1/2 in stage size, blastzone width, and blastzone height (obviously 1/3/1 isn't possible).
2. Variety in the platform layouts. Absolutely nothing is repeated and there's no significant skew towards "cramped" or "open" which means the majority of matchups should be able to find a very agreeable stage on this list.
3. It has some of the appeal of the Melee formula while still being different enough from Melee. You can easily strike to Battlefield like you do a million times in Melee, but with the variety of platform layouts and many more diverse matchups, there is plenty of room for all the neutrals to get decent use.
Here's what's possibly problematic about this list of starters(although at some point, ya gotta take what you can get)
1. People are stubborn and may not be able to be convinced that Smashville as a counterpick is a good idea.
2. There are 3 walled stages to the 2 non-walled stages. I suppose if someone is purely trying to get a walled stage, it might be a problem because they're guaranteed to get one. I don't buy that it makes that much of a difference. I HIGHLY doubt that there is a character that is simultaneously A. Good on all three of WL/GHZ/DS and B. Significantly reliant on walls as opposed to a good stage layout.
Atlas, I just want to add that WL and GHZ are decently small and PS2 and DS aren't THAT much bigger than they are small. The average for stage width for these starters comes out to around ~141, which Battlefield is only slightly below. In fact, I could compare it to your starter list. The width gained by replacing SV with DS is made up for with the width lost by replacing FoD with WL. Blastzone wise, they're fine too, with WL and DS being reasonable outliers and PS2 and GHZ having ceiling heights inversely balanced with their stage sizes.