The ALC meter is a meter that shows how much limiting the ALC circuit is having to do because you're over-driving the input Marconi. If its set correctly it should show nothing at all other than a slight flicker on voice peaks.
How to set your radio up properly for SSB TX.
1) Either use an external power meter that has peak hold or use a tone generator app on your phone to generate a constant tone around 1kHz at normal speaking volume level.
2) Set the TX power to 100W.
3) Set Mic Gain to 0. Yes zero as in none, off, nil, nada, zilch. Turn PROC off.
3) Start transmitting, either talking if you've the power meter or by playing the tone with the phone at the normal distance you hold your mike from your mouth.
4) Increase the mic gain and continue to increase it until your power meter is showing 100W on peaks.
Congratulations you've just correctly set up your radio for transmitting in SSB and I bet that the mic gain is somewhere around 25% at most. Increasing the mic gain will not provide any benefit. It will not make you sound louder, it'll just make your signal wider and dirtier. Reducing it does not make you sound quieter in SSB, it just decreases peak TX power. In fact when I used to do real QRP below 1W I used reducing mic gain as a method of reducing TX power. Nobody ever said I sounded quiet even the 5/7 report I got from Argentina 7500 miles away with 1W or the 5/5 report I got from Italy, 1200 miles away with 250mW.
I also noticed that you have the pre-amp on. Turn it off because your background noise level is S5 with it on. Without the pre-amp on if your S meter is showing anything other than S0-S1 background noise you don't want to be turning the pre-amp on because you don't actually benefit from anything and in fact you lose out as you decrease the dynamic range of the radio. In fact what you'd normally do is use the RF gain to REDUCE gain when you have a reading on the S meter on an empty frequency. On a CB you'd do it until the meter showed S0, on a ham radio because of the way the S meter works you would do it until the S meter went up fractionally then back it off a little. Yes stations will sound quieter but you increase the AF Gain/Volume to compensate and weaker signals will be easier to copy because the unwanted noise is attenuated more than wanted signals. You don't increase RF gain either by winding the RF gain up or turning on a preamp because all you do is increase the unwanted background noise and you don't actually make weak signals more copyable as a result.
Unfortunately like the ALC meter being right over, having RF gain whacked up to 11 and pre-amps on seems to be one of those bad practices that has somehow found its way into the "correct way to do things" even though it actually is the polar opposite of what you want to be doing. Pre-amps are completely pointless on HF because the noise floor on the quietest place on planet earth on the quietest HF band, 10m, is -120dBm (the level of galactic noise) which is S1 and your radio is capable of hearing well below that without the pre-amp on. Pre-amps only have benefit on VHF and higher where the noise floor is considerably lower. Incidentally the reason that CB receiver specs show SINAD at -120dBm is because that is the level of galactic noise on 11m so any weaker signals will be drowned out by the QRM from space.
