Even without modding, KR has a lot going for it as far as functionality and ease of use over 2d. Eg, the equip/unequip functions make it very easy to very brutally abuse +skill items. In an item based game, KR's inherent hotkey/macro system seem, to me anyways, vastly superior to 2d. You can simply outhotkey the 2d/uoassist setup.
I feel I must inform you that pre-specified macros in UOAssist such as Bandage Self, Drink X/Y/Z Potion, Arm, Disarm, Take off hat, Dress/Undress, and a status bar showing health/mana/stamina as a changing colour-coded bar (High, Medium, Low), as well as a count from anything to gold, weight and Armour Rating to Number of regs and arrows/bolt in your UO -title bar- have been around for years, and are vastly more responsive and less complicated than the macro feature in KR.
There is no revelation to be heard from the KR macro system, and I consider UOA to still out-class it by leagues, as a long-term user of UOA who can say this from experience, and a current tester for KR.
The KR system is riddled with bugs including unresponsiveness, to just outright not doing what it's told. I set macros to bandage myself, and to cast chivalry spells; despite not specifying what to target, everytime I tried to use these abilities it would tell me I cannot see that / cannot perform beneficial acts on that target. Whether or not this is because it may default trying to target my CURRENT target (Which is just stupid, and should leave it on your cursor for you to decide by default), in which case every cast/ability macro needs a 'Wait for target' icon at the end, I don't know. I'll try that in the morning but I had to settle with dragging my spells and bandages to the hotbar, assign a hotkey there, and right click again to change who it would target by default.
Further to all this, the 12 hotbar assigned keys remain the same throughout the scroll of the bar.
If you fill up the first bar and assign macros, then add more to the second bar; they will all have the same hotkeys, and so to use abilities on other hotbars you will need to physically swap to that hotbar; or just place all abilities on a 'new hotbar' that will be placed somewhere on your screen and takes up way too much room.
And with regards to any comments about "Yeah but UOA costs so you're a loser on that point" - It costs $15, or £7.50 for me; a one-time fee I paid for out of my (at the time) £20 a month allowance YEARS ago and still reap the benefits for. So, money really isn't a factor.
The final ball-ache to add, is that unlike 2D, KR doesn't seem to save individual character's macros or interface setups anywhere, and so you have to re-configure everything from fresh when logging onto a character for the first time, instead of being able to copy a macro.txt file from one characters settings folder to another.