Well it's good you took a course, very nice to see some people expand there minds. It also makes my job easier
Anyways speaking in terms of planetary gears it's a science!
For example the carrier, you have a choice of aluminum or steel, the benefits are of there materials, steel is stronger but heavier, aluminum lighter yet weaker then the steel. Then the number of planets, the more planets you have then the more torsional strength of the planet so the more load you can place on the planet, the issue with having more planets generally more then 3 is that it may not be very precise and there can be some vibrations from the planet now of course with wear the planets will wear down and begin to spin more truely and vibration will decrease.
Also if it's a stright cut or angle cut, and how many degrees is the angle, straight cuts are stronger but produce more noise, angle cuts the opposite less noise at the expensense of durability of course you can substitute with more planets OR having it cut at a lesser angle say 15 degrees. I could literally sit down for hours with a white board and show you designs, materials, anything and everything. The stock planets are simpson style planetaries well most are.
I personally am happy with the 6 planet aluminum carriers, they hold up well, even when towing! Generally you will want to switch to steel if you do some serious towing or any type of racing mostly drag racing.
The next thing you want to look into is the overrunning clutch or commonly the sprag, you want to change out the cam (outer race) and get one that is a bolt in, SMR transmissions sells a kit for the 46,47, and 48. The reason being is because the stock cam is just a press fit and if you shock load the transmission (loss of traction then traction) the cam could easily break loose and rip the case apart.
If you go into anything performance like that you are going to want to replace the forward drum and direct drum, if the overrunning clutch was to fail then the forward drum would spin 2.2 times as fast as it's input speed which would cause the transmission to explode which is EXTREMELY dangerous!
As far as ring gears, the stock ring gears are usually a medium carbon steel and are heat treated. They have to be in order to support the load.
As for the converter, you can't just shell out a stall speed, it's going to be based on so many variables hp, torque, the rpm of which they are produced, vehicle weight, gearing. It's pretty complicated, but you can think of it like this, if you race use a higher stall speed, if you tow or just a daily driver a low stall speed will do fine. I run a 2000-2200 stall and it gets the job done.
As for line pressure, it's going to depend on variables like anything. Math had to be used to engineer the machine so math or atleast some logic is going to be used to modify it, that's if you want it right.
The reason for no shift kits, because most of the kits require you to drill holes in the valve body. Now doing simple valve changes like sonnax manual valve, regulator valve, and throttle valve is ok because those are to correct common issues more then affect the shift timing.
You can change line pressure to increase the shifts, I can't tell you what PSI to set anything to because the line pressure changes in relationship to the pump and the valve body itself, this is why there are test ports on the outside of the bell housing in addition to diagnostics.
If you want my opinion on clutchs, alto red eagle and use there kolene steels. I won't use anything else they are the best period dot.
Seal kits, transtec is all I use, there kits are pretty complete and they aren't expensive at all so why not.
Another thing I do it's odd but: For the front band I use borg warner and the reason why is because of a few reasons inexpensive, thick friction material layer so last longer less replacement, and have more surface area. Then for the rear band I use raybestos hi energy, why because it works and I don't use reverse as often as my drive range so wear to the drum won't be significant at all. The original bands in the 95 and earlier use to be made by advanced friction materials who was actually bought out by raybestos in later 95 early 96.
Stay away from kevlar or carbon bands unless you have the money to replace drums.
Bushings, use clevite cannot go wrong with them for dam sure!
if you want my fluid opinion, this is just my opinion: Valvoline ATF+4 it costs a pretty penny but all atf+4 does!
another thing i do is install an external cooler of course because these tf's run pretty dam hot! also remove the anti-flow valve helps increase flow and reduce the risk of overheating due to a lack of fluid.
there is just so much I could write about the torque flite, great transmission but if you're going to use it in competition performance it needs some work, other then that I have seen 727's behind vehicles with over 1000HP. another issue is the number system, they say 46rh right so 600 ft-lbs but remember the torque converter multiplies torque of course it's in proportion to speed so as the TC speeds up the multiplication decreases and vice versa. this is something many people forget about is the torque converter multiplying torque, now of course you can exceed the limit but for how long is the question.
anyways you ever have any questions you know you can always ask me im more then happy to answer questions or lend a hand anytime, transmissions are something i really enjoy. i work only with torqueflites so im limited.