Paladin:
Conversion, about 9.
Holy freeze, 20 (everything is easier when slowed down).
Charge, 20
Zeal or Vengeance, 20
Holy shield, 5 at least
A prayer mercenary to heal you and keep fire enchanted ones away from you. Charge is fun and strong and with a close attack you need not fear being caught, and you can vary your tactics and not be easily bored. Holy freeze gives you a second damage type and conversion and holy shield will make everything more convenient. Vengeance handles dual immunes. Your town guard will benefit tremendously from conversion and slowing to aid him. Use a Nadir helm to cloak when needed, keep a wand of weaken or life tap for bosses and tough uniques, get a source of open wounds or prevent monster heal, and there should be little that can stop you.
Necromancer:
Golem mastery, 20
All golems, 1 (perhaps some more points to clay golem if you favour it)
Bone spear or spirit, 20 (bone spear can be aided by the cheap White rune word, and is usually more economical)
Bone prison, 20
Decrepify, 1
Rogue mercenary to deal a third damage type and weaken enemies with weapon effects as well as aid golems with inner sight. She will hang back and not accidentally be caught in prisons. A recastable golem, bone prisons and curses will keep the heat off her and you. Very little can resist magic damage and the party will have access to three damage types by themselves without even counting equipment. Put a point in poison dagger and stab the enemy with a malice kris if they regenerate too much. Decrepify enemies or send them running with terror. A synergized bone armour will allow a few mistakes here and there, like wading into a barrage of quills for example. There are points to spare, which might be used to build up the synergies with bone wall for more defense or build them up with the missing one of bone spear/spirit for more diverse attack options. Or put everything into clay golem and laugh at its ridiculous hit points and slowing.
All in all very little dependancy on items, diverse damage and some effective crowd control options.