Hmm, sounds like you are struggling with some of the same things I did early on... I am not sure the reason for your hesitance to go with the setup to have different actions tied to the press versus the release of a key. I cannot put in words the impact this little tweak to my setup for the looting and collecting of quest objects has made to my enjoyment of otherwise painful collection quests for a team of 5. I encourage you to give it a shot and see what I mean, unless you have some particular aversion to the technique...
If you compare what you have which requires that you press 3 keys (I am not including the follow for reasons indicated below) to get a char to loot to my only pressing 1 and multiply that times anywhere from 8 to 24 (and even higher at times) pieces needed for a single quest, couple that with the fact that not all items have a 100% drop rate and then consider all the collections quests that exist in LOTRO.... Well you can see where some of my priorities are... Of course, everyone has their own set.
To comment on your configuration though, you do not need an additional step for the F2. You can combine that with the U which is what I am doing and it seems to be working very reliably... The /Follow I have on a different key (mouse5 for my setup) and there is not really anything in the looting process that will cause the follow to break, so for the most part that is not needed. In fact, I can actually have my team loot on the run with my single key loot setup. With my 5 RK team I am able to actually kill most normal mobs while moving and have the following characters loot the mob as we run by. Essentially, I rarely have to stop running while I move around the countryside laying waste to the masses. Just to illustrate, yesterday, my 5 RK team and another player (guard) went into the swamp near Ost and killed enough trolls (approximately 250 trolls) to finish the troll deed as well as our enmity of the trolls deed (dwarf race specific deed) in less than an hour and a half of questing in that area, which included running the bounties set three times and all the other collection quests. We did this at level, so the mobs were same or higher level that our team. Between all the crawlers, flies, orcs , undead and trolls that we had to mow through I would estimate that we went through somewhere in the neighborhood of 500+ mobs... This is both a statement of the efficiency of the single key loot / interact key mappings as well as my new love affair with a 5 RK team...
For your gather setup, similar things stand out. you can combine the F2 with the U on the same step and the follow is probably not needed as a normal part of the sequence. If you stay with the setup of keeping things on separate steps, this would at least reduce your step count down to 2 which will be much easier to keep synchronized with what you are trying to do at any given time...
As for "time between actions" I am not sure I follow your question. The only timing that you can control is how fast you press (and for me release) keys and I do not really consciously think about it when I am using my new loot / interact mapped keys. So, that is to say that I am just pressing and releasing each key as you normally would in typing.
The "face target" issue is only a problem when fighting or interacting with something and not for looting. In fighting this is not generally a problem unless mobs run up to and past my group and then hit from behind which does happen at times. I overcome this by turning my main and then just having the group step backwards a few steps until all have line of sight again. For interacting with something I run my main up to and just to the side of the object and then turn to face it. This tends to get the rest of the group to a point just in front of it and in position to interact without issues... It has taken me a bit of practice to learn the most efficient move for my particular play style, your mileage may vary of course...
Hope that makes a little sense and is helpful...
Cheers,
creo