What's the intended usage? Not just 'now', but over the next year+.
You mention an HTML front end, but if it will only be used by yourself or a small number of other admins, it's probably better to simply create standalone scripts for each task, they can always be scheduled by cron/whatever if they need to run at a specific time.
If the intent is wider use, possibly by the fat-fingered, then I suggest before getting into the Meraki specifics, you need to figure out how you will handle secure access/authentication etc., log everything and harden the platform against accidental/malicious misuse.
For tasks that are 'dangerous', consider a creating some kind of permissive action link so that at least one other admin must approve before execution.
Have an automated script that regularly grabs API usage across all the orgs, check for unexpected/unauthorised activity.
Figure out how you are going to secure/manage API keys.
Generically...
Use Python, it may not be the most efficient runtime, but it can still max the API rate limit.
Use the Meraki Python library, it tracks the production API pretty closely, if you need to use beta API you can still leverage the library by making a compatible function in your script.
Sanitise/validate input data as fully as you can before making any change, it's better to not change anything than to exit part way through a batch of changes, watch out for unicode, there's a lot to be said for sticking to ASCII.
Use UTC for the linux system and all time-related activities, tracking umpteen timezones and DST changes is a pain.
Log everything, for tasks running autonomously have them alert the admin(s) if there's a problem, I use email.
You say you have a Linux VM, document every step needed to recreate whatever you build.
Have a separate development/test system, i.e one VM is not enough.
How are you going to back up the VM(s)?
Consider creating a private Github for the project, that you/others can use.
Lastly, do you really need to develop this? There are Meraki ecosystem partners that provide this type of thing, it may be more cost effective/supportable to use an off the shelf solution.