I don't think this offset should be calculated automatically, because depending on what's going on in the air column in might not be as simple as a 100m:1c offset, especially in cases of inversions. But by showing the model elevation I can make those evaluations for myself.

Right now, I cross reference SpotWx to get an idea of what to expect at the location I'm actually headed to. But needing to reference a free service to get this data makes me wonder why I'm paying for a premium version of this one.

Here's an example. Windy is reporting GFS temperatures for Tuesday morning as -15 for both 1400m and 2900m. There's probably a 15 degree spread between these locations, and I have no idea if -15 is the valley bottom or glacier temp, until I look at SpotWx, which tells me that the model is for 2050m. So valley bottom is something like -9, and the glacier location is probably something like -24.

So my suggestion is to put 'Model Elevation' somewhere visible in both the single-model and 'compare' views.

I should add, I am a part of the mountain guiding community here, and many guides here use and recommend to clients a combination of free and other premium services as a consequence of not having this information readily available in Windy.