Mike and Sencillo, good points
One thing though, Mike you write about 12 and 14m2 in 12-14 knots ? (assume you are average weight since you dont write)
That could be fine for the very first attempts, yes.
But I would say it is waaaaay too big
I use a 9m2 (average weight 75-80kg) in this wind, in warm summer wind.
And a 10m2 could be used in 12 knots maybe, but my 11m2 (depower wavekite) is too big and I never use it in that much wind...
In fact you could ride with a 7m2 if you wanted, in 14 knots, no problem (but an 8 or 9m2 fits perfect).
Sencillo is right, use a smaller kite (NOT 12-14m2) and a bit longer lines if light wind.
Apart from being able to waterstart and get going easily cause of the long sweep so you can focus solely on the board - you also wont get overpowered as you WILL be with a 12 or 14.
And last but not least: Even if the wind drops, you can keep your kite in the air and NOT have to swim/drift ashore
The longer lines, say 27-32m or something, will make you able to downloop the smaller kite very easy in extreme lulls, and you have a big bufferzone so you wont end up with the kite in the water.
I've seen numerous trying with 12 or 14m2 kites and normal 21-24m lines, and they always ended up with the kite in the water, even when a bit experience and able to ride - untill they found out that the kite was too big and clumsy - a no good for hydrofoiling
Remember, you ride about two kitesizes smaller on a hydrofoil than a TT, so when on a 12 on a TT you are on an 8m2 on a hydrofoil.
Meaning, say a 14m2 kite, is okay powered in winds maybe 8-9 knots on a hydrofoil.
But you would normally go out in say 15 knots on a TT with a 14m2 right ?
Above means the 14m2 in 8-9 knots behave like a pig, heavy and clumsy, wont turn at all because of this light wind.
So you lose all the power you could have had when looping the kite - which you can do with a smaller kite much better and same power, and way more fun to turn and carve with a responsive kite.
So you dont lose anything with a tad smaller kite a bit longer lines in terms of start power, but you win a lot in terms of handling and you will never get the kite in the water.
A win-win-win IMO
When you get experienced, you can ride with normal lines again, as you most often choose the correct size - but you will lose a lot in terms of low end and ability to "survive" lulls, so maybe not good actually...
When the wind is even lighter, dont go with a "classic" 12 or 14m2 - it does not work...
In light wind below 10 knots, use a "light" lightwind kite like the Dyno or Edge and similar, when 12m2 or more in size, or much better a foilkite of course.
Otherwise it will only be a question of time till it ends up in the drink.
A 10m2 on a bit longer lines, will often be able to stay up far better even in marginal winds
Again, like Sencillo said
When you are good, and want to race, you will rig up in size again of course, and have to learn to control this - eventhough the kite is too big for normal carving and freeriding and fun.
Just some pointers that very few new are aware of, as the sizes are so much on your "backbone" that it takes long, and a lot of swimming, till you find out yourself