macbook pro for video editing

Hello,

I'm looking to get one of the new Macbook Pros and will mainly use it for video work (using FXP with 4K Slog footage from a Sony A7rii), as well as some photo editing in lightroom.

I'm looking at the 13" MBP with the specs listed below

• 2.3GHz dual-core 7th-generation Intel Core i5 processor
• Turbo Boost up to 3.6GHz
• 8GB 2133MHz LPDDR3 memory
• 256GB SSD storage1
• Intel Iris Plus Graphics 640
• Two Thunderbolt 3 ports

However, there's an option to upgrade the CPU to 2.5GHz dual-core 7th-generation Intel Core i7 processor, Turbo Boost up to 4.0GHz or an option to upgrade the RAM to 16GB 2133MHz LPDDR3 memory and was wondering if I had to choose one, which one would better help my efforts.

I'm currently using a macbook air to do all my video work, which works for the most part but I'm looking to start editing larger videos (20 minutes vs 8-9 minutes). Not too worried on how long it takes to export, just want it to render quickly while editing.

Any help is really appreciate.

Thank you