I think there needs to be higher level titans and the titans themselves don’t have to actually be stronger. This can make titan hitting more stronger and possibly utilise greater strategy .
My suggestion is a titan that rotates it’s element / colour every 30 seconds . The possibilities for higher level titans could be
Level 15 2 colour titan - ie red/green
Level 16 3 colour titan - ie red/green / blue
Level 17 4 colour titan- ie red/green/blue/yellow
Level 18 5 colour titan ie all 5 elements
This would require different strategies than solely just mono colour require different strategies to tackle it than now and best of all does not require power creep of titans and hitting the titan would have different make up of team than any current raid / as ‘ titan team and would provide a unique challenge to the top teams.
With this type of setup they could release 50-100 levels for titans in one hit and not bother about titans ever again as they can do the above rotation type at 4/5 star level titan and increase it higher
This could even enhance importance as such heroes as the soon to be released gazelle which can change colour or enemy