What's with Into the North and the snow lands? I don't see a Scrying Sheets or Extraplanar Lens, so it seems like you'd be better off running vanilla basics and Rampant Growth.

I wanted a higher chance of ramping from 2 mana to 4, in order to give me a consistent ability to play Rashmi in turn 3. The sooner I can play her, the sooner I start benefitting from the triggers.

I don't disagree with the general argument, but Rampant Growth is also cmc=2 ramp. The difference is that it hits any basic, whereas Into the North can only hit snow lands. You've only got 6 snow lands, so late game it's possible that you'll have nothing to find in your library for Into the North. If you replace those snow lands with vanilla basics and Into the North with Rampant Growth, you won't affect your probability of ramping from 2 to 4, but you'll reduce the probability of the spell being dead if you draw it later in the game. It's not a huge difference, but I'm pretty sure it's a net positive.

Or maybe you have some other snow synergy that I'm missing?

Oh wow. That's actually a complete brain fart from me. For some weird reason I thought Rampant Growth was 3CMC, which is probably why I never went back to look at it when I was adjusting my ramp spells.

I actually just double-checked the physical deck to make sure I hadn't added it in and then forgotten about it in the list.

I think the more likely solution is to replace one of my mana rocks with Rampant Growth, and then eventually aim to replace all my basics with Snow basics. That way all my ramp spells can hit any of the basic lands, and it allows me to keep Into the North, since I'd actually prefer to weight my ramp towards spell-based, due to my local metagame. Extraplanar Lens is still under consideration, but I'm not really sure what I'd cut in order to fit it in, and I don't generally find that I have a huge amount of basics out most of the time.