For me, as an instrumental music lover, the main and possibly the hardest goal you want to achieve in making such music is to NOT make it seem like it could be just an underlay for something grander; therefore to make it in such a complex and creative way so it just feels entirely complete - like it doesn't need vocals to reach its ultimate form.
"As the Love Continues" is a record from the rock spectrum, so the listener will naturally seek to hear a vocal line to complete the well-known sound of rock guitars and percussion, which only complicates the situation, requiring an even higher level of attention to detail. And that's where the new Mogwai's album falls short. Although the opening track, "To the Bin My Friend, Tonight We Vacate Earth", is a fantastic, absolutely respectable instrumental piece, you can already sense that it would not be an adventurous record. All the following tracks, apart from "Ritchie Sacramento", where we actually receive a couple of vocal lines, are affected by the problem I mentioned earlier - for nearly a whole hour, "As the Love Continues" sounds like a backing track on a regular, fully "vocalized" rock album, only without the presence of any voice. The instrumentation is not adventurous enough to entertain you in a way the vocals would have, and the very pieces are sequenced similarly to the standard songs: verse - chorus - verse - chorus - bridge - chorus, you know it. What's even worse, the "verse" parts are actually quieter, so they just C R A V E a human voice.
So, this new Mogwai's record is undoubtedly a very quality and just solid album when it comes to production, instrumentation, or even musicality. It just generally lacks creativity, which makes it a very unsatisfying and incomplete experience. Not a bad record, though.
[If you want a fulfilling, completely rewarding instrumental record, check out Snarky Puppy's "We Like It Here" - I will worship this album forever, it's nearly perfect, it's enthusiastic, mind-blowingly creative, and just fun as hell.]