FTXL
First Trust Nasdaq Semiconductor ETF
stock NASDAQ ETF

SPY, SPLG, and VOO all track the S&P 500. VTI tracks the whole US market, but 84% of VTI is the S&P 500. VTI is the simplest option, but if you want to control the weighting of funds you can do SPLG + VXF and that will replicate the total US market but at your own custom weighting.
QQQ is the Nasdaq 100. It's pretty heavily weighted in tech. Has done great for the past 15 years but also extremely volatile. Seems unnecessary, really, unless you want to overweight on these companies since you'll already hold everything included in QQQ by purchasing VTI or SPLG.
FTXL is just semi conductors which is a pretty high-risk play. I generally wouldn't recommend something so narrow in a portfolio. Though if you think it's a strong option, I'd limit it to 2-5% of your portfolio.
VXUS is the standard ex-US international fund (basically like VTI for the rest of the world). And BND encapsulates the bond market.
To answer your first question, I'd say these are fine (except FTXL, IMO, because it's not diversified enough).
For your second question, don't bother trying to time the market. Unless you're planning on throwing $1M into this portfolio tomorrow at all-time highs, whatever you start with now will only be a drop in the bucket to what you end up with over the next 20-30 years of regularly investing.
As a side note, if you just want a simple 60/40 portfolio, AOR is just that. You can get what you want by just buying that 1 fund. Or you can look at how it's composed and mimic that.

VOO, SPLG, and SPY are the same thing - stick to SPLG. It has the lowest expenses.
SPY only makes sense if you are option trading - if you're posting here, that doesn't apply to you so dump it.
If you have strong opinions on semiconductors FTXL is fine, otherwise dump it.
Overall - VTI/VXUS is going to cover all of your wants and needs without a problem.

VOO/SPLG/SPY are the same. FTXL -no, VXUS-no, won't come close to S&P with these 2.
QQQ-OK, but prefer XLK or MAGS.

SPY, SPLG, and VOO all track the S&P 500. VTI tracks the whole US market, but 84% of VTI is the S&P 500. VTI is the simplest option, but if you want to control the weighting of funds you can do SPLG + VXF and that will replicate the total US market but at your own custom weighting.
QQQ is the Nasdaq 100. It's pretty heavily weighted in tech. Has done great for the past 15 years but also extremely volatile. Seems unnecessary, really, unless you want to overweight on these companies since you'll already hold everything included in QQQ by purchasing VTI or SPLG.
FTXL is just semi conductors which is a pretty high-risk play. I generally wouldn't recommend something so narrow in a portfolio. Though if you think it's a strong option, I'd limit it to 2-5% of your portfolio.
VXUS is the standard ex-US international fund (basically like VTI for the rest of the world). And BND encapsulates the bond market.
To answer your first question, I'd say these are fine (except FTXL, IMO, because it's not diversified enough).
For your second question, don't bother trying to time the market. Unless you're planning on throwing $1M into this portfolio tomorrow at all-time highs, whatever you start with now will only be a drop in the bucket to what you end up with over the next 20-30 years of regularly investing.
As a side note, if you just want a simple 60/40 portfolio, AOR is just that. You can get what you want by just buying that 1 fund. Or you can look at how it's composed and mimic that.

VOO, SPLG, and SPY are the same thing - stick to SPLG. It has the lowest expenses.
SPY only makes sense if you are option trading - if you're posting here, that doesn't apply to you so dump it.
If you have strong opinions on semiconductors FTXL is fine, otherwise dump it.
Overall - VTI/VXUS is going to cover all of your wants and needs without a problem.

VOO/SPLG/SPY are the same. FTXL -no, VXUS-no, won't come close to S&P with these 2.
QQQ-OK, but prefer XLK or MAGS.