Generally for a loan to be approved the bank will evaluate you base on your net income which is your gross salary minus commitment.
Usually banks can check your commitments via loans with other banks but that is about it, if you pay alot of things via cash the banks can't trace thus won't take into account, e.g.
1000 salary no commitment then bank will base on 1000
2000 salary with 500 housing loan then bank will base on 1500
2000 salary with 500 room rental the bank will base on 2000 because rental is cash base they cannot track

if you find yourself having difficulty getting your loan approved then you need someone as a guarantor like your parents (better if they are working, if retired will be abit more difficult in terms of documentation)

generally banks will approve if your net salary is able to cover two months repayment, e.g.

RM34k loan x 3.5% interest rate x 5 years = 599
RM34k loan x 3.5% interest rate x 7 years = 453

so 7 years is more likely they approve.
Yes, I think so.
If kept as 2nd/weekend car should be okay.
Daily drive I don't encourage.
Japanese make sports coupe usually would be a better option for a daily drive.

If you like to be in a coupe then do check out the cars below 

2008 BMW 120i - usually i see sellers having the 118 which is fine but you get more kit and power in the 120 plus the engine is similar to the 320 thus compatible parts always means lower prices for parts, however when i say lower price for parts don't go thinking it is going to be cheap to keep like a kancil it is a BMW afterall so eventhough it is an older model with R&D amortized the prices of parts are decently priced but still premium. Think of the price range as somewhere between a Mazda3 and Mazda6 in terms of part prices -- especially for big ticket items however routine service parts are cheap.

2005 BMW 320ci - okay so the car above is abit fugly and expensive. Then how about consider this one? Isn't a sports hatch as the one above it is a true coupe. Just as nice and of course just as rare so you'll still get a glance or two when you roll up in one eventhough it is a 10 year old model. This is the last chance for this model (after this over 10 years kenot loan) and at 48k it is worth considering as you get a coupe body, good looks, good engine which is shared with the regular 4 door 3-series thus parts are cheaper to obtain.

2007 BMW 323ci - sitting somewhere between the two above in terms of price and year, I consider this a good buy, might consider it myself. This coupe from from the e92 generation just before the current f30 generation, infact I think the f30's were inspired alot by this model as the front and back end do have similar looks. So you know what that means right? Common engine and gearbox platform means cheaper parts and the exterior looks that still look fresh now, especially since it is so rare.
Thanks for bringing this up.
I did some checking and found THIS very informative article. It seems that the CVT overheats if throttled too much which leads to premature death of the gearbox. It seems the current models have fixed this issue but a large proportion of the cars in used car dealers still suffer from this issue. The fix was adding an oil cooler, I don't have the numbers yet for workshops cost to install this but found someone in LYN selling it not too expensive.

Well, if you do drive spiritedly I guess it is a no go for Sylphy. Gotta think up of an alternative......

2011 Honda Insight - a value for money buy would be this hybrid since it will help you save fuel and isn't too old. With the tax laws as it is we will probably not see a replacement for the Insight any time soon thus it won't readily get "dinosaured" like more mainstream models as City or Jazz. However, a caveat is "according to people" it is a ticking time bomb with a CVT gearbox that can explode anytime and also a Hybrid battery and trasmission system that can fail anytime. People fearing that have caused the RV for this model to plummet like a rock which is why it is so cheap.

2011 Honda City - of course a more traditional car with more traditional setup might suit you if you want to play it safe, however this model is widely known to be not so frugal when it comes to fuel consumption. However, both cars are Honda's so picking either one would be a good choice as maintenance wise they aren't really that expensive.
Signs to spot a flood damage car

With that budget you can also consider this car.

2006 Mitsubishi Lancer GLX - this is the import only model which Mitsubishi Malaysia sold for sometime, perhaps it wasn't a good bargain as a new car because there were better cars at this price point but as a used car less than 30k for a Japanese CBU car, it makes you have a nice headache. They're pretty cheap to run and is a C-segment as you wanted, I think they look better than the Altis -- but you'd probably find that the Altis is cheaper to maintain.
For 50-90k, why not up the budget abit and buy something like the HRV?