I liked the Wakanda battle but the Titan was leagues better as you said. I think it had to do, in part though, with the way that the Titan battle varied from the usual formula. Typically in Avengers films, we've seen the epic battle where The Avengers crush a ton of cans and the only threat was the sheer volume of the villains rather than what they actually brought to the table. Wakanda battle fit the same template even though the Outriders at least appeared to be more dangerous than the Chi'tari and than Ultron's pawns. Plus there was at least the added factor that Black Dwarf, Proxima, and Corvus were shown to be extremely formidable and were involved in that battle. But otherwise, it definitely felt like the typical Avengers large-scale fight.
Titan battle was far more focused- with several heroes taking on the big villain of the film. So unlike the typical heroes taking on an overwhelming number of villains who are individually no match for any of them, you had some very powerful and effective heroes banding together to take out a far more powerful entity wielding the most powerful weapon in the universe. The early portion with the team work with the implementation of Quill's plan was absolutely awesome, the weight of the moment where Starlord flips out was well-acted and tense, and the mano y mano segments with Strange vs. Thanos and Stark vs. Thanos were tremendous.
