Thank you for mentioning Tower! I would just like to add that Tower 9 also included many improvements around the merge/rebase experience, including an Instant Conflict Detection that should satisfy the "preview" workflow mentioned.
I work at Tower and I recently put together a "Tower versus Sourcetree" comparison page (there are many features that Sourcetree is missing): https://www.git-tower.com/compare/sourcetree/
Tower offers an "Instant Conflict Detection" feature that should be right up your alley (I work at Tower, a Git client for Mac and Windows).
It will let you know in advance if conflicts will occur when merging another branch or revision (by merging, rebasing, or pulling). Here's an example: https://imgur.com/a/VCkqrBI
Thanks for posting this interesting article. I work at Tower (Git client for Mac and Windows) so I feel compelled to chime in! :)
Becoming more productive with Git is one of our main goals, and I'm happy to state that most of the operations you address are already included in Tower (apart from "sync", which we will think about internally).
As for the others you mentioned:
reword - you can edit any commit message from the currently checked out branch by right-clicking the intended commit and selecting "Edit Commit Message"
split - you can edit any commit from the currently checked out branch by right-clicking the intended commit and selecting "Edit Commit". You will then be able to reform that revision into one or more new commits.
preview - Tower offers an "Instant Conflict Detection" feature that will let you know in advance if conflicts will occur when merging another branch or revision (by merging, rebasing, or pulling). Our latest major update was focused heavily on creating a better merge experience and you can also see the number of unresolved conflicts that you still need to resolve (with a progress bar being shown in case of a rebase). If you mess things up, you can also undo the latest operation or abort the Merge/Rebase operation altogether.
undo - you can undo pretty much any operation with CMD+Z (or CTRL+Z on Windows). This includes not only commits, branch creation/deletion but also more complex operations like merges, rebases, and even file discards (which is not something Git actually supports).
large-load - Tower works well with large repos. We do build caches on first run, so the initial run might indeed take longer to display very large sets of data (e.g. 10k+ tags).
large-ops - We designed Tower from the ground up to remain responsive when doing any kind of operation. All commands run asynchronously, so you can e.g. push a branch and immediately checkout another branch simultaneously.
I hope you give Tower a try in the near future — feel free to get in touch with us if some other question pops up.
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