[l_johan_k]

Why is a methyl radical sp²- and not sp³-hybridized?
Wouldn't it be more favourable to have the unpaired electron at a further distance from the bonding pairs?

[AWK]

Try VSEPR

[l_johan_k]

Try VSEPR

But wouldn't VSEPR indicate that the radical should be sp³-hybridized (since the angle, between the unpaired electron and the bonding pairs, is 109,5^o in the sp³-hybridized structure, but only 90^o in the sp²-hybridized structure)?

[AWK]

But also you can consider sp2 and  1 electron on unhybridized p-orbital

[sanderol]

But also you can consider sp2 and  1 electron on unhybridized p-orbital

ditto.

It can be sp3, although not with a methyl radical. But if it has electronegative substituents on the radical carbon it gets more sp3. Reactionwise this will not change a thing since the inversion energy is very low.