In case you don't know, "Flexi" is a popular short way of saying "Flexible" and fits perfectly with "Bet" both in meaning and in aesthetic pleasure.
Just a quick interjection from me, unfortunately I haven't followed the whole discussion here enough to provide more input.
In German, "flexible" is abbreviated to "flex" and I seem to remember that this is also the case in English. As a result, "flexbet" would actually be a simpler and easier to read alternative to "flexibet", where I would agree with the previous poster that the "i" interferes with the reading and memory flow.