Guardian Saint does nothing in solo play [unless you place it directly under some other player on the same map without him wanting it xD] as it just shifts damage from one player to another player for x hits (3-21 maximum during 60 seconds; 90 seconds CD though).
You could make use of the SP/Stamina regeneration increase by simply placing it under anyone randomly as stated above, but that’s basically it, because it requires two players to work…
To lift your illusions on Cleric C3:
It doesn’t work wonders unless it’s in specific builds.
15 heal tiles will not prevent people from dieing, it will only make it a little harder [but it will make it easier for you to become top damage dealer as you can use heal offensively and still have left-over tiles for others to heal with].
Your Safety Zone also doesn’t get any better if you’re just putting 5 points into it. 5 points are 52[skilllevel]+102[attribute] hits blocked, for a total maximum of 34 hits [counting Divine Might and Houki Broom buff], the same as C2 Cleric has got.
Divine Might at 5 also has no pros above C2 Cleric.
Fade on 1 is nearly useless [you don’t really need it because Taoist has got Dark Sight,though], while a lvl 10 Fade could be kept up eternally with Dievdirbys’ Laima buff…
In the end only Heal&Cure damage are worth it for damaging builds.
There’s also the option of Pardoner to make some $$$ with Daino Scrolls.
Kabbalist C1 is not really worth it unless you want to save money on SP pots or boost your survivability by increasing your max HP/blocking 1 attack every ~40 seconds with R7fold.
Oracle is still the quirky Oracle with lots of skills at C1 that are not so useful. Prophecy is really good,though, because it protects you from getting “status-ailed”. That’s ± the only weakness your current build has, because if you’re caught with Sleep/Frozen/Stone Curse you’re disabled until it wears off. Let’s hope you placed Aukuras nearby to help with this 1st, otherwise feel free to enjoy several controlless seconds. Status ailments aren’t that bad in TOS,though, so maybe Oracle isn’t needed anyway [unless you like RNG-rerolling and tanking magic damage from within Counterspell].
You could also choose a very unpopular one like Sadhu C1 to deal damage with OOB autoattacks [which aren’t affected by Blessing, thus don’t use up Blessing hits while dealing continuous damage with autoattacks based on your matk], stagger+mob monsters with Astral Body Explosion and move your body around with Praktiri (useful to flee from enemies attacks if you can leave the AoE in time that way).
Or Paladin C1 for additional HP&SP regeneration and resist elements, which boosts your magic damage by reducing the magic def of nearby enemies.
Don’t forget Smite&Turn Undead, as they’re quite useful as fillers/killers,too, even on non-patk based builds (if you’re using maces that is,though).
Or go Bokor C1 for Effigy-spamming while your other skills are on CD /gg (not recommended because it will eat your SP like ftw).
There are so many possibilities and it’s hard to make a solid choice at the current state the game is in. We’re ± halfway content-wise [lvl 330 of 500-600 planned, Rank 8 of at least 11 if not 12 planned] and we don’t know what other classes can/will be offering later on [especially new attributes can power up seemingly useless skills like Merkaba e.g.], so just watch some videos and choose the one Circle with the best skills 
