HoN kept the deny xp loss and the gold lost on deaths from DotA1 unlike LoL.
When you deny a creep, not only the opponent will not get gold, but he will win only half of the xp if he's a ranged character, or 2/3 if he's a melee character (that's also why suicide characters are mostly melees)
When you die, you lose an amount of golds, slowing down your item progression.
This adds (compared to LoL) deeper tactics, for instance lane control characters are really efficient, despite not being able to engage or solo anyone, because they are very good at denying, cutting opponents' gold and xp. Also you can have plenty use of gankers even early on as they can focus totally on denying the opponent hard carry, so he will spent all the game dying and will have to spent left money to buy cheap items, slowing down his progression.
Also, compared to DotA2, it's much faster actions, animations and overall speed are faster, making the game more intensive. You can skip animations on most characters, but it can become very efficient on some of them. For instance, pyromancer (equivalent of Lina Inverse) will cast his 3 spells (stun -> wave -> ulti) in 1.4+1.4+1 = 3.8 sec if u queue up but if u skip animation it becomes 0.8+0.6+0.2 = 1.6 sec, so his burst time is halved. A lot of people dont like HoN for this reason, having to spam to skip animations in order to be competitive.
The community is as bad as LoL so no difference on that