This was an ending that could have used a little more thought most certainly.
DS9 'fixed' for want of a better word the problem. One unlike the Host where the symbiote completely subsumed the personality of the host, in DS9, the Trill joining was a blending of personalities, with each new host contributing something new. Riker/Odan may not necessarily have had the same feelings for Beverly that the original host/Odan did. The second thing was that DS9 came up with the Trill rule that relationships didn't pass from one host to the next. There was not meant to be any rekindling of past loves from past lives.
Then DS9 addressed the issue by having Dax break that rule. And teenage fanboys got the girl on girl action that made them happy.
DS9 'fixed' for want of a better word the problem. One unlike the Host where the symbiote completely subsumed the personality of the host, in DS9, the Trill joining was a blending of personalities, with each new host contributing something new. Riker/Odan may not necessarily have had the same feelings for Beverly that the original host/Odan did. The second thing was that DS9 came up with the Trill rule that relationships didn't pass from one host to the next. There was not meant to be any rekindling of past loves from past lives.
Then DS9 addressed the issue by having Dax break that rule. And teenage fanboys got the girl on girl action that made them happy.