Well, it has been said about every class
"aps need heavily prepping, dont ever try to play them without huge sack of preps"
"as an assassin you need a lot of preps to win blah blah blah"
and such
same for paladins. But in this case I think its not completely true. You have good inherent protections as a class
what you might need (but you can live without it):
reduce/enlarge/fly - to avoid bash/trip. not hard to get.
shield potion - can live without it, just avoid big ganks and Ravon.
stoneskin - very easy to get especially when you are paladin - just go, and buy a dozen of fillets.
teleport potion - 1 gold coin.
that is all.