Meraki is good if you're background isn't networking and you're responsible for managing the switches. You'll have to keep a close eye on the license expiration, as you'd hate to be in a position where the license expires, and you're no longer able to use your gear.
Couple questions that'd I'd ask:
- Are there plans to have multi-gig Wireless AP's in the future? (for 802.11ax)
- Do you currently have routing configured on your existing 3750 stack? You're routing config will determine if you need the Layer 2/3 switches.
- Do you have a lot of East/West traffic for high volume traffic? (Storage? AutoCAD? Really Bursty traffic?) stacking bandwidth may come into play here.
- Any 10/40/100GB interface requirements?