The front cover leak is a result of a failed or improperly installed seal. Fairly easy fix, but takes some time.
The hard shifting is a result of low engine vac or leaking vac lines. Pull the air filter housing and replace all the rubber parts of the vac lines, and you will shift smoother. The AC will also then work better, and you will cure some of the idle roughness, too!
Check the hoses on the idle control valve (under the air filter housing) -- they get hard and leak even though they are still attached.
Tranny leak can be a leaking actuator seal or the front pump. If it is the front pump, you will eventually need a new tranny (not really repariable). At any rate, expensive. You will need to crawl under and find out where the leak it, it may be a simple as the dipstick tube o-ring.
Brakes will feel funny for a while, til you get used to the ABS. A little bit longer travel than you are used to, and a sort of dead zone where you don't seem to feel more pressure, but increased pedal travel gives more braking. This is normal.
However, if you need to apply a large amount of force, you may have a leaking brake booster and/or booster line. This will also give you low vac (and hard shifts, AC vents that close on accleration) and hesitation.
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!