S. R. Faruqi:

nufuur = Hating, fleeing from.

To call someone who despises the towospeople, or flees from them and wanders around, a 'house-wrecker' (whose house would already have been destroyed, or who would destroy the houses of others) is very fine. The second line is laudatory; it suggests that to hold oneself aloof from the townspeople is not such a bad thing. Otherwise, Mir wouldn't have been called a good person. The enjoyable thing is that on the surface there's nothing of praise in the line-- only from the tone does it become clear that Mir is someone worthy of praise.

Then, it also appears that despite being worthy of praise, he's a house-wrecker; perhaps good people are destined particularly for house-wrecking. Then, he hasn't mentioned the reason for house-wrecking. The reason might be the madness/wildness of passion, or it might be the aloofness from and aversion to the commercial give-and-take of the material world. In the speaker's tone there's also a light touch of envy. The verse is basically one of 'mood', but through the play of suggestions so many meanings have also come into it.

FWP:

SETS == NEIGHBORS
MOTIFS
NAMES
TERMS == MOOD

What SRF says about 'tone' in the second line reminds me of the kind of affectionate abuse ('Why, that old son of a bitch!') used in English too in colloquial speech. Using 'man' for aadmii catches the colloquial flavor, but please note that aadmii doesn't have the macho overtones that 'man' can easily acquire. (Women are aadmii too, in nineteenth-century Urdu, and call themselves so in perfectly normal contexts.)

The fact that the (active) 'house-wrecker' can just as easily be the (passive) 'house-wrecked one' also adds to the ambiguity, especially because the houses the mad lover would wreck almost certainly include his own, which would give him a claim to both epithets at once. And despising and fleeing from the people of the 'town' is plausible behavior for the mad lover in either case. The verse reflects the realistic but broadly sympathetic view that the mad lover's neighbors have about his doings (in the world of Mir's ghazals).

When it comes to questions of tone, this verse strikes me as one that really, definitely does have a 'baked-in' tone. It's hard to find another way to read the second line except in the ruefully admiring tone that SRF proposes. For more discussion of this question, see {724,2}.