In reasonable seas, the Tasman 20 (20') I cut my teeth on could sail to windward, with the tiller lashed, on headsail only, allowing the main to be reefed. I never had an autopilot or self-steering, and did some reasonable trips single-handed.
When the risk of being put about at an inconvenient moment meant the above procedure was not possible, (eg in big seas) the same boat hove to nicely under headsail with the main luffing, allowing the reefing job to be done quite easily if it wasn't blowing dogs
Don't assume it won't heave to in big seas if it doesn't immediately fall in your lap: I reckon experimentation in less severe conditions initially, and gaining familiarity with how it handles in bad conditions, will probably see you get on top of it if you persevere.
Make sure you ease the main so far it cannot fill, and adjust your headsail and tiller on that basis, so that when you start lowering the main, the balance is not unduly disturbed. Ignore the noise!
I say this because balance is more critical for small boats. With a big boat, it's generally fine to heave to with the main intermittenly filling, in preparation for putting in a reef...
I personally think it's undesirable to rely on the motor
for any singlehanded sailing tasks, especially on a small boat where they're generally unreliable.
In any case, it's unlikely a small autopilot and a small engine
will be able to keep a small boat head-to-wind when it's really blowing: it's not a trivial job even on a big boat and needs quite rapid "hard over response", and on a small boat when it's blowing hard you pretty often need to slew the outboard
to 'catch' the bow when it starts to lay off the wind unwantedly.
But even on big boats, using the motor singlehanded to do sail handling jobs is asking for a rope
around the prop, because when there's only one of you, you can't be everywhere at once.
[ I often throw the tail of halyards overboard
, abeam of the mast
exit box, when dropping sails
singlehanded: this ensures they won't tangle. Can't do this sort of thing with the engine running... ]