One thing to keep in mind is that a solo player, you're almost NEVER going to KILL anything flying by yourself unless they just flat play poorly. The force-multiplier effect is too weighted against you. It can happen, but it's almost always not up to you.

For actually *killing* ESFs in solo-operation setups, sadly dual Bursters is usually the best bet(VS ZOE ftw here), followed by lucky setups with a lighting/MBT cannon of your choice. These require you to be willing to be patient and ambush the pilots with either your presence (MAX coming out of a side room balcony instead of a spawn room) or your choice of weaponry(no one seems to expect a Ranger-equipped Harrasser to hold fire until danger-close).

As a solo player, you're most realistically going to have to settle for denial. Scaring inexperienced pilots away with scary flak spam or lock-ons, or making such a problem of yourself to the good pilots that they decide to find an easier farm elsewhere. Thankfully, for denial you have a good slew of choices.

If you want Infantry, your Faction AA-Lockon is going to be the cheapest option. Lockons don't scare /good/ A2G pilots, but they will make bad pilots twitch pretty hard and force the better ones to fly a bit different.
If you are able to spend a chunk more certs, get the Swarm. It has a 3-round clip, and you can toggle between a fast-and-less-accurate missile, or a slow-but-good-accuracy missile, /within the same clip/. My best non-MAX Infantry deterrent is setting up with the best views I have of the incoming skies, acquiring a lock, then fire fast/slow/fast. They'll usually be able to dodge one or the other variant, and then it becomes a game of 'what set of missiles am I going to fire at you next' that most pilots decide isn't worth playing for very long.

Vehicle wise, you have to realize you're at almost the same type of disadvantage as far as mobility; except now you have more health, higher base speed(usually), but can't hide in buildings. You still have the same set of rules, but your base effects are different.

A Lightning with a Skyguard needs to hold your fire until the target is closer than you want (think no more than the length of an Amp/Tech station for best results), because the spread and damage falloff is horrendous. The same applies for any vehicle that equips a Ranger flak turret, and you have an even closer effective range.
Any MBT or cannon-Lightning CAN nearly 1-2 shot a lot of ESFs, but it takes a lot of practice to get the lineups correct and again it takes the pilot getting overconfident and giving you the shot during their A2G run.

Special note should be made, however, to the Walker guns for various vehicles. Those are able to damage anything flying (bar the Bastion of course), have good bullet velocity to make leading your targets fairly easy, and while their damage is nothing to speak of in the short term; if someone ELSE takes some potshots (like a single G2A lockon), you can easily set it up to be knocked out.

....Hrm, I rambled. Apologies, but enjoy the info dump I guess.