To be fair to COTM - I didn't hate it. It's just one of those "eh what am I doin' - wasting time" things. At various times I've felt various things about it - but I never really loved it. Love is reserved for games that I actually feel close to, and COTM just has this layer of blandness that keeps it at a distance.
HoD, though, I actually did love for a while because of how whacked-out the design was, probably in part due to the recycled enemies and the cut-down nature of it (if it had been originally designed for a larger console). Beyond that, though, it had character (odd, but still) and some areas were pretty memorable. COTM has...waiting for blocks to rearrange the sewer paths.
The extra modes (magician etc.) are for people who are REALLY desperate to find something to play. Come on, I haven't found all the times in Vagrant Story yet, didn't get all the parts in Armored Core, haven't played Shadow Tower Abyss, haven't beaten Operation Wolf 3 on one credit yet, and I'm not going to play it again anytime soon when there is new and fresh (at least for me) stuff out there. In the grand scheme of things, CotM was memorable enough as a GBA launch title but shouldn't be on my top games list, no matter what brand it is.