I'm not sure what you're asking, but your strategy is generally sound. I can add some general tips for magplars...I have one.

1. Entropy (mage guild) grants major sorcery, increasing your spell damage by 20% for 12-20 seconds (forget how long). Any magic ability, including heals, will hit 20% harder while this is active, so it's a good buff to keep up constantly.

2. Radiant destruction is your finisher. It slaughters enemies once they're below 25% health. Heal through the battle, then when it nears an end a magplar can step in with some mighty dps. I get like...I don't know...4-6 ticks of 25k+ damage with this. Remember to use Might of the Guild (see #6)

3. Purifying light is a handy skill. It dooms an enemy for something like 8 seconds. During that time, the damage they take is counted and at the end of doom they take an addl 18% of the damage plus your allies get a heal. A lot of Templar skills allow you to weave some dps between your healing abilities.

4. Proximity detonation. Yet another ability you can mash, then let it do its thing while you focus on heals. It's a little tricky to time, but it can deal some significant damage. A healer usually stands between the tank and your ranged dps. When using proximity det, you try to time it to step close to the tank and the mobs with a puncturing jab right as it explodes.

5. Repentance. One of the best skills in the game, IMO. If you're running with stam allies, especially nightblades, the stamina recovery from this can be off the charts.

6. Mage light. This is an optional skill you might consider for your attack bar. It will raise your crit rating about 12%. That means one in every eight casts, including heals, is 50% stronger. I sometimes put it on my attack bar with radiant destruct, jabs and breath of life so that these spam abilities get the crit boost. Also, the mage guild passive Might of the Guild increases any ability cast after a mage guild ability by 20%. When a boss is down to 25% you should be walloping them with radiant destruction, and you should always be casting a mage guild ability before you do.

All of the above skills are candidates for your attack (non-healing) bar. A lot of healers just pile on two heal bars, but I personally find that it's better to round out the character with some solid dps and other buffs. Your heal bar can then include your rituals and the other heals you mention. In the early Part of a tough fight, I'll switch to the attack bar and cast entropy and doom...maybe turn on a proxy det and toss out a repetence if those are helpful. Then quickly switch back to the heal bar and continue working those. When the doom expires or the proxy explodes, it's a good indicator that it's time to switch back and cast another entropy, etc.