Most life peers have considerably more power than most hereditary peers, and, consequently, are almost certain to get more real respect (as opposed to ceremonial flummery). Most life peerages are political appointments: they are a way of giving someone a seat in parliament, for life, without them ever having to be elected by anyone (although many life peers were, formerly, elected members of the House of Commons). Admittedly they are in the House of Lords, which has considerably less power than the House of Commons, but it has real power nonetheless. Being in the Lords also means that life peers can serve as Cabinet Ministers (and non-cabinet ministers), and they frequently do. Sometimes people are appointed as life peers specifically so that they can be in the Cabinet.*
Although hereditary peers can also sit and vote in the House of Lords, and some do, many don’t bother because they are simply not very interested in politics, and, in practice, even those who do bother are mostly considerably less influential than the life peers. Life peers are mostly people who have been professional politicians most of their life (or, sometimes, very successful business people with strong political interests, or powerful trade union leaders, and things like that); they understand and care about politics, and have the contacts. A hereditary peer is just some dude who inherited a title; even if he cares about politics, and votes and makes speeches in the House of Lords, he is unlikely to have either the political energy or influence that life peers generally do have.
The Law Lords - in effect Britain’s Supreme Court - are also life peers (and also get to be members of the House of Lords).
*In Britain, it is the Cabinet that really controls the country, and, apart from being the actual Prime Minister, being a Cabinet Minister is the is the peak of political power. Cabinet members, and all other ministers, normally must be Members of Parliament - Commons or Lords. Very occasionally non-members do get appointed to Cabinet or other ministries, but if that happens, either a life peerage is quickly arranged for them, or some MP in a very safe party seat will be “kicked upstairs” to be a life peer so that his/her Commons seat becomes available, and the new minister can win an easy by-election to the Commons.