You haven’t mentioned how old he is, but honestly, I don’t think you need anything else at all assuming he’s 7 or under. Remember, many places are not even remotely starting to teach reading until age 7. Also, all studies show that outcomes are better for children who learn to read later, than earlier (assuming neurotypical children without learning delays). Learning at 4 or 5 or 6, gives no benefit, no edge, over children that learn to read later at 7, 8 or 9, and in fact, they often end up behind those that learn later.
It’s very easy to memorize a rule, or a simple sound. It’s a lot tougher job to blend them together. I think the worst thing you can do is start overloading a child who is struggling with yet MORE work, another program etc… If anything, back off for awhile, give him time to mature.
What can be taught in 6 months at 6, can be taught in 6 weeks at 7, can be taught in 6 days at 8. If we would just wait until children are actually developmentally ready, the learning process would go much easier/faster.
So… at the most, just continue with what you’re doing and just continue to read to him, every day. Get him some simple BOB books if you want, or the I Can Read It! series is great, if he WANTS some extra practice. Otherwise, if it is stressing him out, then I would back off.
The range of the normal age for learning to read is 4-10. The median is 6-7. There’s no reason to rush it.