Ouch. Sorry I do apolegise coming in all arrogant as a transient visitor among the company of experts within their specialised fields but I just need to correct a few misgivings.
The DB-601 and Merlin aren't anywhere near the same capacity.
The Merlin weighs in at just under 27 litres swept capacity for the early series and just over 27 litres coinciding with the supercharger redesign (ie. from the Merlin X, XII and XX onwards).
The Daimler is a shade under 34 litres.
I think what Red Admiral meant to say, in engineering terms power output is most directly related to fuel intake rather than engine capacity and the Merlin II and DB601A have similar power outputs with similar full throttle heights so it is natural their supercharger requirements may be very similar.
The shift you get between them is torque x rpm = hp so the Daimler being a much larger engine produces the same power output at much lower rpm. This is handy because due to much larger throw weight inside the engine it isn't going to like revving its ring off much. There are a lot of pros and cons you could weigh up between the two approaches, historically they were pretty evenly matched it seems but my ears would start ringing after a while in a Spit I think.
wrt low-comp/high-boost and high-comp/low-boost firstly air cooled radials aside, larger capacity inline engines tend to march their rated altitudes upwards from smaller capacity ones. I guess this has to do with flow dynamics through large bores and no small amount of complex diversity I'm sure.
Smaller capacity engines have less torque particularly as altitudes rise and so may require complex supercharging systems sooner than the larger engine and are thus more limited overall in terms of extended high performance application. A good comparison for this is the 605AS large bore motor compared to the complex Merlin 60-series for roughly similar rated altitudes.
As far as compression ratio goes a higher comp with lesser boost tends to bring the full throttle height back down for good performance at medium combat altitude, whilst maintaining good cruise and climbing conditions at much higher rated altitudes. Best of both worlds without complex supercharging and intercoolers. For maximum high altitude performance however either multiple supercharger stages or an intake oxidiser would still have to be used (nitrogen oxide).
Of course for outright medium altitude high performance applications a charge coolant like MW50 can bring the full throttle height down further to allow significant overboost in the thicker air (ie. it is like using the high supercharger gear in a two-speed engine at low altitude, with the knock index improved by charge coolant), with outputs similar to maximum emergency power at sea level or better. Problem here is glow effect on the plugs which limits its use and necessitates frequent cooldown periods.
Larger bores are also useful in dealing with lower knock rated fuel as you can more effectively shape the piston crown to help delay predetonation. The higher compression ratio in the 605A to the 601E at the same pressures using the same B4 fuel is most likely due to larger bores and better piston crown shaping. Quite a bit of research was performed in Germany on this, and it was decided that was a better result than the increased valve corrosion due to the use of higher octane fuels (unless absolutely necessary).
Finally on fuel consumption at cruise, again comparing the Spit and 109 what you have is two aircraft that'll cruise around at about 2000rpm. Both will have fairly neutral manifold pressure. Ah the Daimler has larger bores you say, it is using more fuel at the same engine speed.
Ah but no I say, it has much more torque, has a rated altitude for cruise a kilometre or two higher than the Merlin unless it is using positive boost, and the increase in fuel consumption is offset by much less engine loading for higher average speeds. These offsets provide similar aircraft range between early Spit and Me109 with similar fuel loads.
Aircraft range as engine capacity increased actually went up with the same fuel load for the later Messerschmitt, probably helped also by improvements in drag, whilst fuel loads had to be increased as the Spit developed to keep similar internal fuel ranges, whilst maintaining ~fairly competitive performance (adjusted by variant moreso than year of issue but I think tending to favour the Spit in the later years bar a particularly nice example, like a clean G-14 fitted with an ASB and Mk103, be pretty nasty for anything short of a XIV).
Here's a nice little paper outlining some of the research into fuel qualities that was going on in Germany.
http://www.fischer-tropsch.org/primary_documents/gvt_reports/BIOS/bios_1612.htm