Well one thing that helps avoid forearm tendonitis is working your extensors as much as you do your flexors. All the clinging grip work works the forearm flexors and tends to make them overtight as well as stretching the extensors too far. This leads to tendon pain and inflammation. Large doses of omega 3 fatty acids, and training your extensors will help. Omega 3 fats are way anti-inflammatory. Also, work on training finger extension (I think that’s the right term)–instead of crimp work and pinching strength try and train your fingers to spread/extend as far AWAY from each other as possible. You’ll need to add resistance of some kind–rubber bands, or something, not sure.
Basically, balance is necessary not only with push exercises but also the forearm/finger extension functions.
As far as other stuff, get stronger at chins in terms of low rep high weight stuff. Work on chin endurance, which you probably already have a lot of. Work strict form bent over rows, dumbell rows. Work whole body lifts such as squat and deadlift for helping your body fire as a unit (another plus is core strength from the whole body lifts). It’s really more a combination of lower volume but more intensity when trying to gain strength. You might really benefit from increased hamstring/hip strength in weightlifting for pulling from heel-hooks and such when climbing–deadlift variations are great for hammie/hip strength.
Stick to an athletic/powerlifting/olympic lifting kind of routine. Focus on compound movements over isolation stuff, b/c they give you the greatest boost to power and strength. Stay away from machines because they are fixed-plane-of-motion and you climb in 3 dimensions. You need the stabilizer work. If you keep strict form and resist the temptation to “ego-lift” you’ll stay safe. www.exrx.net is a great site for form videos, as are many of the articles here. Work heavy within strict form.
I’d suggest variety in your reps from week to week, while staying in the low rep end. Pick a main exercise for each session, go lower reps or heavier on it than your others. Rotate that main exercise every couple weeks.
Keep calories around maintenance levels (you’ll need a daily nutrition log and weekly weigh-ins to get your numbers right). Maintenance level calories will help you recover, but won’t give you too much in the way of material to hypertrophy with. I’d actually recommend sitting about 200 calories above maintenance to help you add strength. At that rate muscle gain will be very slow anyway, and if you’re training with strength parameters rather than hypertrophy parameters you shouldn’t grow much.
Take a week-long break from the really heavy, low rep work every few weeks to avoid CNS burnout and tendon stress as well. Do prehab or really endurance focused sets with exercises you have not used in the last month or so… It’ll help you stay healthy and fresh and ready for the next round.
Sorry for the novel. Hope this helps.