They all do it, Blair brought in loads of new Labour peers when he got in.
Personally I think the whole Lords system is out of date and the politics completely detracts from what they should be there to do which is to scrutinise legislation from the commons.
Personally i'd be in favour of scrapping the whole lot of them and having a fully elected 2nd chamber, but for it to be completely politically neutral, with every member banned from being a member of any political party.
Legislation could then be properly scrutinised and debated so that what the country gets is right for the country and not whats right for whichever political party is in power.
To be fair to Tony Blair (not words you see often anywhere these days) his government did get rid of the hereditary peers in the Lords. One tiny step forward, but then, as you say, several steps further backwards because he appointed a load of so called 'working' life peers himself.
I'm not sure you could ever achieve a completely politically neutral and elected second chamber, however desirable that may sound, because standing for election without the support of a political party behind you is not easy and also quite expensive. Just getting a fairly basic candidate leaflet printed and distributed in a council ward is hard work. Dealing with bigger constituency areas is even harder. Plus, with no party allegiances at all, the second chamber would probably end up resembling a cat-herding conference.
The issue for me isn't that politicians sit in the Lords, it is that whoever sits in the Lords, they owe their positions to patronage, and though many of them work hard and with integrity, many of them also do not, but regardless of their performance, we cannot get rid of any of them, they are completely unaccountable.
Their numbers grow but never diminish.
That just ain't right.