There are many stories in the lives of saints of heretics and persecutors of the Church (Arius springs to mind) who had awful accidental deaths or who "got what they gave" in some treacherous fashion or another.
We pray in the Orthodox Church at every liturgy and at other services for "A Christian ending to our life, painless, blameless and peaceful, and a good defense at the dread judgement seat of Christ."
There are traditions (especially monastic ones) that there is a relationship between the holiness of one's life and the peacefulness of one's death. This is of course not at all an absolute. But we are encouraged each time we see it. Having had the opportunity to observe a few of those peaceful deaths, there is something to it.
It is very fitting to keep the "last things" constantly before the faithful. In the Lutheran tradition such prayers are the beginning of daily Compline ("The Lord almighty grant us a quiet night and peace at the last") but daily use of Compline is rare in most parishes. There is also a petition in the greater Litany asking deliverance from "an unprepared and evil death."
Actually, I think the logic does apply to the holy martyrs. Their deaths, borne with fortitude, accepted for Christ are their glory.
The evil death, whether in pain, or in peace, is either fought by the dying, the more vigorously the greater the sin, or embraced with despair. The former is usually explained in terms of sin attaching us more firmly to this earthly life, but I suspect in the clarity of facing death, even the evil have some intution of the need to repent, and the need for more life in which to do so. The latter is absolute pride, since such despair refuses reliance on God even when no alternative of self-reliance or reliance on the other false hopes of this life remain.