Ok, but you didn't say which software you use; if it is a matter of software, maybe you use synthesizers and then connect them to the MacBook.
I don't think it's a problem (in case you were thinking of using Reason, which is just an example anyway) with this processor; the sound card is important because it practically solves latency problems. Just today I was trying with Reason 3 a digital piano connected via USB to the PC, 2 GB of RAM, dual-core at 2.8 GHz, 500 GB hard disk, but there is still a bit of delay—not much, but you can hear it, especially if I use instruments like the piano or the harpsichord.
I don't use an external card nor an internal one, but rather the audio acquisition of the motherboard, which from this leads to the impossibility of improving things for now.
But I am mostly talking about live performances; in recording, I don't even use the connection with the piano or a synthesizer.
My points, in fact, are not exactly criticisms—indeed, you have highlighted them in quotes—I don't have much experience with software, but I have been using Reason for many years without ever using post-assemblies (as in analog synthesizers, so to speak), without the various functions that facilitate the "creation" of patterns for both drums and parts of other instruments or synthesizers, so I use it in an alternative way; I use it and I have always used it to make both electronic and instrumental music pieces, and it is not easy for the latter.
The thing I don't like about Reason is the impossibility (still current, and I don't understand why they don't change this parameter, which is essential for me during the composition phase, though I think I understand the reason why they don't touch it) of setting less than 1/16 as the unit of measurement for a bar; for example, if I wanted to set 1/64, I couldn't. This has nothing to do with the notes, so it is possible to use 1/64 notes; then, obviously, it always depends on the metronomic tempo, but this deficiency, in light of all the functions the current version has, is why I haven't updated it since version 3.
The designers don't change this parameter (I think) because the product is aimed at those who make music without composing it in a "traditional" way; this is my thought. For them, it is enough to record everything and modify the tempo (it is possible to do so from version 4) and things are done, but if there are specific indications in a composition, if I were them, I would do it. That way, even if VSTs cannot be imported, since Reason itself is imported by software that has the Rewire protocol, I would have many useful functions at my disposal, even in the absence of score creation or VST import.
Usually, people (from what I hear) work well with Logic Pro; it depends on the approach anyway. Maybe I'm the one who is sick for using this software—which 99.9% of people use for dance or other genres—to make "quasi-baroque" style music and other things.