Hearthpwn

I want to make an ideal, straightforward deck for F2P players, that would be viable at least till rank 5.

Still not sure with few cards - opinions?

Try to find room for Consecration. There isn't a single midrange deck I know that functions effectively without a board clear. Find space for at least one. I'd also agree that some type of healing card is needed. Cheapest option would be Guardian of Kings because its free; you could easily swap out an elemental or Stoneshaper for it.

As for getting rank 5, it would be possible if everyone was playing the same list as you. Other Paladin decks will simply have more value than yours, aggro Paladin will out-tempo you, etc. It's really just not in your favor. I'm sorry for being pessimistic but the fact is, certain cards (especially legendaries) are just too strong to not auto-include. This is why aggro is so strong, the decks are just so cheap and can pump out wins much faster than a sub-par midrange deck. I would honestly advise crafting Tirion or Tarim before even taking this on ladder.