A well rounded team of 4* heroes can do very well against Titans. But I do agree that’s a long time to still not have your first 5*. I started last May, and got my first 5* on a lucky coin draw in mid June. No others until last month when I rolled 30x in the event summon, and only got 2 more.
If you’ve not already, work towards getting Training Camps to level 20 to try for free 5* heroes! My luck has been poor, but I did finally get Horghall out of a TC20 a few weeks ago.