I'm not arguing with the general premise that Hadlee was one of the greats, but I'm not sure about the advantages or otherwise of playing as a lone bowler vs as one part of a great attack. Hadlee had a lot of things in his favour - he got his choice of ends every time, and had a large say in when and how long he bowled during the innings. He had plenty of opportunity to bowl at the opposition tail. He probably got to choose the particular ball that felt best to him... Plus home wickets and arguably umpires tended to be fairly favourable to him. It's hard to know what his figures would have been as a part of a better attack, maybe fewer wickets, but at a better average?
He would have got the choice of ends regardless in any side. He being a pace bowler also meant he was limited in spell so unlike Murali, he couldn't just bowl and bowl and bowl and bowl. As for home wickets, that's every single bowler though, look at the pitches in South Africa at the moment, if that's not suited to their bowling attack I don't know what is. Because he couldn't just bowl over after over after over, any time form batsmen got stuck in, he'd invariably be the one to winkle them out - so very few times unless he ran through a team, would he get the chance to be bowling at new batsmen in each of his spells. As for umpires being favourable to him, might have something more to do with the fact that he didn't appeal for the ones he didn't think were out, his wicket to wicket line and length meant he was constantly an LBW threat.
In the case of Murali, he still had Vaas for the majority of his career who was more than capable as a seam bowler, and invariably most of his wickets came on dust bowls against opposition that weren't happy in the sub continent. The great players of spin found him pretty easy to boss around, such as Lara. Hadlee, no one really found his bowling easy, he was always a threat.
Hunting in packs gives bowlers immense advantage, pace bowlers especially. McGrath was always a much better bowler with Gillespie at the other end performing - the same can be said about Steyn and his combination with Morkel and Philander. Spin bowlers like Warne come along very rarely, where they're able to bowl either in a pack situation with someone like McGrath, or put in a virtuoso performance in a side that was losing most games (2005 Ashes) due to skill, style and mental strength.
Shane Bond would no doubt have performed much better if he joined this current NZ bowling attack than the one he was part of.