Habitica for Training
Honestly I don't use Habitica for my training, because training is my destiny. I'd rather use Habitica to support my training goals with non-training Habits and Dailies. But if you were to use Habitica for training, here are two ideas I have. The first is a Habitica Choice Daily,
Basically put in 90 minutes of training total per day. Could be a 1 1/2 hour lifting session, or 1 hour of lifting in the afternoon and 30 minutes of working on the splits in the evening. Mix it up if you like, but get it in. One other way, which I've used myself, is to create a + only Habit for twice-daily training.
Set the difficulty of it to HARD so you get big rewards for training twice in one day!
Basically if I trick, I get to check off the Daily. If I don't trick, I have to do all the other things on the list, which support my tricking, to check off the Daily. With this Daily I am supporting my tricking goals... Daily! Whether I trick or not!
The only Daily that has been a staple in my own Habitica setup has been one called Stay healthy, it helps motivate me everyday to eat super foods like garlic, kale (cruciferous vegetable) lemon and ginger (Detoxigest) and supplement with vitamins and healthy fats and spices like cinnamon.
Blood pressure is important to monitor for health reasons, especially as you get into your 30s. Bodyweight is an obvious form of progress checking for bulking or cutting. If you are trying to build muscle you should also measure your body parts (waist, chest, bicep, legs) to see if you are indeed growing where it matters, if at all. You would only need to do this once every two months though. Also, taking a photo of yourself posing at the same time every Sunday morning can reveal physique changes if you are bulking or cutting. I'm sure you can think of things to add to this yourself!
There are a lot of ways to use Habitica to support your training, let me know if you have any great ideas!


Tricking
My favorite way to use Habitica for tricking is to use a Habitica Choice Daily, this one in particular:
Recovery modalities
Using Habitica as a motivator to do the ultra boring auxiliary activities and recovery work that support your training goals, is one of the best ways to use Habitica for training. Add in things like,- Foam rolling (self-massage)
- Light stretching
- Cardio for active recovery
- Prehabilitation exercises

Health and dieting
This Habitica Choice Daily may meet your needs quite nicely for leaning out:

Injury rehabilitation
I wrote about this on the page Habitica for Injuries, take a quick peek!Progress report
Here's an example of one to do once a week, maybe on a Sunday.
Training journal
You can use Habitica to remind you to make an entry in your training journal once per week. Possibly set it for Sunday?