Pardon my butting in but, I'd like to point out something from the Autodesk side of the fence. I've been a techie for 2 different resellers and while I haven't been brainwashed, having worked with Autocad in places ranging from Alaska to Dublin, I can see where they're trying to succeed with this problem.
Autocad (as well as most Autodesk Products) are made for a WORLDWIDE audience of users. The way they do things in Dublin are completely different from the way they do things in places like Portland, OR, Phoenix, San Jose, New York, and a host of other places I've worked.
The best thing to do instead of sitting back bad mouthing the program and how they don't fit your miniscule issues is to put in a Wish List item. Then you'll see either others putting in responces of how they worked around it OR, someone else with the same problem and wishing Autodesk will fix the problems.
Now, don't get me wrong, I know they can't go in and fix every single leaderhead we want to draw with and some people will just have to learn to adjust their drawings to the Autodesk or Industry standard.. Really, to have 2 different thicknesses of linewieghts on one arrowhead?? Make a new arrow block, assign it a name, and start using it as a workaround. But, then ask yourself "Is this something a multi-billion dollar company is going to put the manpower towards when those same folks are working night and day to make major improvements to all the various programs they're developing and acquiring from other companies.
When all else fails, look for lisp routines on this and other websites that are free to modify (for the most part.. I've never charged for a lisp routine, paying it forward so to speak). Sometimes, you'll get a lot of people telling you it can't be done but, then again, you might run across one guy sitting in a dark office with 6 computers running all around him that will pop in and say "Just change this to this.." and presto it's done.
Once you get the answer, be sure and post the fix here on this website or on one of the other websites you may have posted the question on. Someone might be able to use part of that code to do something else they want to do as well.
Then... one day.. They'll issue an Express Tool with your routine (or one they've cleaned up for that worldwide audience and you can smile and be on your way.
Give a man AutoCad, and he'll draw you a floor plan.
Give a man Revit and he'll build you a house.
Give Cadmama a couple of drinks and she'll have everyone singing Rockytop!