Start small, think big later...
If there were only one piece of advice to give, it would be to "start small." Take the time to get to know the game with a low-cost ship, and if you really feel the need to move up to a larger ship, then simply upgrade your current ship to the one you're aiming for.
Of course, you might be tempted to start with a more advanced ship, but remember that it's easier to upgrade a ship like the Aurora to a Titan or a Nomad than the other way around. So unless you can take advantage of a promotional offer that gives you access to a higher-class ship, be reasonable, and stick with a $60 starter pack (There was a time when the Starter Pack was $40, but CIG has aligned itself with the market and raised the minimum price of the starter pack).
Take advantage of a great discount
Price is a deciding factor, but the availability of a discount is even more so, especially if it comes with bonus content like FPS armor or a ship skin.
However, keep in mind that you risk losing this discount if you melt down your pack. Think about this the next time you feel like changing ships and melting down your starter pack to rebuild it. Additionally, the discount usually comes with a "warbond." This means you'll need to purchase the pack with real money, not in-game credits. If you're a new player, this isn't a big deal, but if you want to take advantage of a promotional offer to upgrade your old game pack, keep in mind that you'll likely have to reinvest the full price of the discounted pack, and your old pack will then be converted into credits that you'll need to find a use for.
Take advantage of bonus content
Bonus content, such as insurance, UEC bonuses, the Hangar, digital goodies, and/or Flair, etc., are elements worth considering while they're still available—especially when they're part of a promotional offer during events like the IAE or ILW. Among these additional features, you might have...
An insurance extension
A pack typically includes 6 months of insurance; in some cases, this insurance can be extended up to 10 years, or so-called "lifetime" (LTI). This is a factor to consider, but don't view it as a requirement, especially since the ship insurance system is designed so that, even if your ship is LTI, you'll likely find yourself reviewing your insurance coverage very quickly once you're in-game.
An exclusive skin
It's always nice to have a special edition livery for a ship, but again, keep in mind that this paint will be specific to the ship in the pack. If you ever decide to upgrade your ship, you'll be stuck with the skin, and it won't be of much use unless you purchase the ship again (online or in-game).
An UEC Bonus
Starting the game with more credits in your pocket will always provide a safety net to cover initial costs, but as many will tell you, credits are easy to earn—don't choose a pack just because it offers more UEC.
FPS gear
Even though it's easy to gear up, it's always nice to start the game with armor, a weapon, or even a multi-tool—which is becoming increasingly essential. Especially since this gear is account-bound. Of all the bonus content a game pack can offer, this is, in my opinion, the most important.
But never forget that...
The ship should always be the deciding factor!
Regardless of the pack's contents, its discount, the bonus items it includes, etc., the ship is the factor you must absolutely consider above all else. I won't be rewriting the article on choosing a Starter Ship here—I encourage you to check it out—but keep in mind that choosing the wrong ship will have a much greater impact on your gameplay experience than a bonus FPS armor set or a few extra credits.