Photos Across 3 devices without iCloud (or partially using iCloud)

I have been trying to figure out a good way to handle my photos while travelling.

I have 3 devices:

• MacBook Pro with High Sierra
• iPhone 7 (latest IOS)
• iPad Mini 4 (latest)

I take most of my photos with my iPhone and a digital camera. When i photograph using the digital camera, i shoot raw (or raw + jpeg).

I have just decided to use Photos as my main photo asset manager (provided i can work through these issues), and as such I'm in the process of migrating from Lightroom. However, I've hit a stumbling block: cloud sync is not an option for me while i'm travelling - the raw photos are just too big, and the wifi networks too slow.

My ideal workflow is something like this:

1. Take photos with iphone, sync to MBP and Ipad via iCloud (or iTunes).
2. Take photos with SLR, sync to Photos via MBP, then to iPad via iTunes.
3. Sort photos on iPad, including favouriting and organising into albums. I would like this work to sync to my MBP Photos App.
4. Edit photos in Photos app, and on iPad. For this, I require the raw files (So can't sync to ipad using icloud).
5. Edit photos on MBP in Photos (after sync from iPhone).

I don't need all my SLR photos on iPhone, but don't know of any way to only sync up to the cloud on a device, instead of up and down.

If i weren't shooting in raw, there wouldn't be a problem as icloud was working fine before until i started trying to sync my camera photos.

Can anyone recommend a potential solution to my problem?

Thanks heaps

Greg