With this mod the long inserter is now obsolete. Do you have any ideas how it can be useful again?

"Adds a GUI for customising inserter pickup/drop positions."
Actually any inserter can be a long inserter using the GUI and changing the pickup/drop position ;)

It's faster then yellow and cheaper then blue, so it has some applications before you can mass-produce blue ones

Very true

having red inserters is also useful when importing vanilla blueprints or to quickly create blueprints that are compatible with vanilla, so that i don't have to switch to another map and recreate a layout when i want to share some layout with other people who don't use this excellent mod:

many (or even most) of my inserters still have standard reach/pickup/drop/etc, and (at least if some modified inserters are not time critical and don't need filters/stacks) i like to use red inserters to indicate that that inserter has different distances or angles.

that's also why i am glad that red inserters now have returned to behave as vanilla, instead of 1 or 2 weeks ago being placed as default with reach 1 only.

with vanilla based stuff, as previously mentioned, Red is faster than Yellow (I think the speeds are 0.01 for Yellow, 0.014 for Long and 0.02 for Fast)

Bob's Logistics mod includes an inserters overhaul that replaces the long handed inserter with red tier 2 inserters.
In this configuration the mod SHOULD (have done some basic testing) modify a placed blueprint to use a red inserter and the correct long reach. If this isn't the case, please report to the forums, where I check daily.

There is technology issue, if I use my blueprint with long reach yellow inserter from previous game I dont need to research log reach inserters because blueprint will set them long reach without proper technology discovered.

Just FIY. Maybe you consider it as important and try to solve this bug. :)