The altar is Dwarftown is never chaotic. If you enter the town chaotic, it will be made neutral, IIRC. If you try to convert it, the townsfolk will attack you. They can't sac you on a chaotic altar anyway though--dwarves are lawful so they can only sac you on a white altar.
Altar generation in rooms is random. Chaotic altars are not more likely to spawn in corners than other altars. If the altar is along a wall but not in a corner, and the room is not too small, you can usually maneuver the monster to stand on it without too much difficulty. At worst, you can dig around the altar to make a bit of space if you're really desperate to sac there.
Kicking stuff onto altars is slow. It will also destroy your potions. Best is to just lock the doors of the room, drop all, pick up all. You're at risk for two turns at most, but that's the price you pay for being chaotic. For the extra paranoid, use invisibility.
Hoping to win with every class, doomed. Archer, Barbarian, Bard, Beastfighter, Druid, Elementalist, Farmer, Fighter, Monk, and ULE Priest down.