One thing to be aware of is the term "broong dtang" - to mix and match. Broong dtang is a Thai term which they use in cooking. And if you don't know, the Thais love to throw the salt in, and the sugar in, and the chili in, and the lime in... They love to mix and match to make food tasty. They feel if the food is very tasty then the people eating the food will enjoy it and be really into it, in the sense of interest. Broong dtang.
One of our teachers used the word for the meditation practice with regards to reflection meditation, to broong dtang, to make it interesting. So that means you can combine reflections, you can combine death reflection with Compassion/Lovingkindness. Think of how some people can die, then do a Compassion/Lovingkindness wish for everyone who dies that way. You can combine the two as you wish. You can do your other reflection similarly. You can always combine with compassion, after all, that is the essence of the Compassion/Lovingkindness wish, to reflect on Dukkha. So in that sense, yes, you can combine death with Compassion/Lovingkindness in a broong dtang reflection.