not sure about this exact application but rear has more general effect on the ride comfort than front. I would not think it would be a good idea to mix types of shocks unless it has been tried before. (and with the price of these shocks I would not be the one doing the experimenting!) If the ride is uncomfortable I would think the likely culprit would be the rears. Of course those are the ones that are more expensive! Not sure I under stand how "front rides higher than the rear-end, and this distributes too much weight to the front and compresses the springs somewhat." If the front is riding higher then the springs are compressed less not more. It could be a result of the different shocks. If you are finding the ride to harsh I would think the answer would be to change the rear to comforts (assuming they are softer). It may feel that the harshness is coming from the front but it usually comes from the rear. It could also be somthing else perhaps a good shop could clear it up.

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Currently
1991 Mazda Miata 174000
1991 Subaru 189,000 Winter beater

got rid of:
1984 VW Vanagon 195,000
1976 350SE Euro 185,000 KM
1973 280SE 4.5 (boy do I regret that)
1980 280SE European W126 4 speed manual (miss it)
1989 BMW 735iL 119000 (good riddance)